Fundamentals of soldering technology and heat treatment of carbide tools

Soldering of carbide plates. Instructions

High-frequency soldering is carried out due to the fact that the molten solder spreads in the gap between the parts of the part that need to be connected. It should wet the soldered materials well and also spread easily over the surface of the product. Solders must have good ductility and high strength. A prerequisite when choosing solder is corrosion resistance. It is important to note that the coefficient of thermal expansion of the solder and the materials being soldered should not differ greatly. Solders are divided into five types, distinguished by melting point:

1. Particularly low-melting (melting point up to 145 degrees);
2. Low-melting (melting point from 145 to 450 degrees);
3. Medium melting (melting point from 450 to 1100 degrees);
4. High-melting (melting point from 1100 to 1850 degrees);
5. Refractory (melting point over 1850 degrees);

High-frequency soldering in most cases is carried out using medium-melting solders: silver, nickel, copper-zinc, etc. Copper can also be used as solder. We will consider the above solders, which are suitable for carrying out such a process as HDTV soldering, in more detail.

• Copper (usually M00 or M0) has excellent fluidity and allows you to obtain a connection of sufficient strength. As a rule, it is used as solder when joining parts made of alloy or carbon steel, nickel silver or cast iron.
• Copper-zinc solders can be used when soldering a large number of metals. They have a low melting point, which allows them to be used even when soldering parts that cannot be heated to high temperatures.
• Silver solders have a low melting point (up to 860 degrees). This type of solder has high strength and excellent electrical conductivity. Silver solders have excellent wetting properties. Silver solders are used when high-frequency soldering of brass, copper, steel or bronze products is required. However, in most cases, silver solders can be replaced with less expensive ones.
• Nickel solders can be used for soldering alloy, carbon and stainless steels. This type of solder is used for soldering high-frequency products made from heat-resistant or corrosion-resistant alloys.

Solders are an essential component that allows you to solder and make strong connections.

Many metal products are processed with high-frequency current; soldering cutters is no exception. Induction soldering is distinguished by its special quality, since, due to the influence of high-frequency frequencies, the structure of the metal is not disturbed. In addition, with the help of HDTV equipment, soldering of cutters can be done in a shorter time, and most importantly, this will not at all affect the quality of the product.

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There is also a more economical option for soldering cutters using a gas torch. But, often, this method does not show the result that can be achieved using high-frequency current. HDTV processing produces a higher quality product.

Soldering of cutters is used in all enterprises dealing with turning production. This technological procedure is necessary in order to solder carbide inserts onto turning tool holders. Using HDTV, local hardening of the tool is also carried out, and parts are soldered with hard solders.

Cutters soldering technology

Soldering of cutters is carried out under the influence of high frequency current and in special induction equipment. There are several ways to solder HDTV. Let's take a closer look at each of them:

1. Stationary soldering. The product is fixed in the inductor in a stationary state.

2. Soldering with movement. The product or the inductor itself rotates, thereby heating a large area

We have already said that a cheaper way to solder cutters is using a gas torch. As a rule, it is used by enterprises with a relatively small budget. Induction equipment is more expensive. In addition, the induction installation, as we found out, has great advantages. And it’s not only about price, but also about quality, since at the end you get a product that will serve you for a long time.

3rd STAGE - SOLDERING THE PLATES.

This stage is the most critical, since if it is carried out incorrectly, during operation of the cutter, the hard alloy plates can bounce off or break due to cracks formed during soldering.

SOLDER.

Solders used for soldering carbide plates must have a melting point of

300° above the temperature arising during the cutting process, maintain strength and ductility at the cutting temperature, have good fluidity and ensure rapid heat dissipation from the carbide plate to the cutter rod.

The following solders are recommended:

To ensure good wetting and spreading of solder over the surfaces of the parts being soldered, to remove oxides and protect against oxidation, flux is used.

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Borax is recommended as a flux, which must first be melted, crushed and sifted through a fine sieve. Borax should be stored in closed containers that protect it from moisture and contamination.

Borax is used either in powder form or in the form of a paste consisting of three parts by weight of borax and two parts of petroleum jelly.

Brass solders are soldered with a flux that is half boric acid and half borax. The melting point of such fluxes is 750 ºС.

When soldering with silver solders, a flux consisting of 43% calcium fluoride and 57% boric acid should be used.

COMPENSATION GASKETS.

Expansion gaskets are necessary to reduce thermal stress. They arise when soldering carbide plates of various thicknesses and sizes onto cutter rods. Large gaskets are used from low-carbon steel or permalloy (iron-nickel alloy). Gaskets are in great demand when soldering the most fragile high-titanium hard alloys.

Features of working with galvanized products

Soldering galvanized tin in a purely technological process is no different from the previous one. But the technology has its own subtle nuances that affect the quality of the final result.

You cannot solder galvanized steel with solders that contain large amounts of antimony. This substance, when in contact with zinc coating, creates a weak seam.

It is better to use boric acid and zinc chloride as flux. If the products themselves have already been tinned with tin during the production process, then rosin can be used as a flux.

When a connection is made between galvanized iron (sheet) and wire, the latter must be bent at a right angle to increase the contact area of ​​the two products.

The rest of the process is carried out exactly the same. By the way, it doesn’t matter whether the wire was made of galvanized or ordinary steel.

There are several more important points that must be taken into account in the process of soldering galvanized products. If solder rods based on tin and lead are used for soldering iron, then it is better to add flux based on zinc chloride and ammonium chloride. The ratio is 5:1 respectively.

Tin and cadmium based solder requires caustic soda as a flux additive.

If galvanized iron products, the protective layer of which contains more than 2% aluminum, are connected to each other, then solder based on tin and zinc is used. And hydrochloric acid and petroleum jelly (stearin) are used as flux.

Regardless of which parts or assemblies are connected by soldering, it is necessary, after the process is completed and the seam has cooled, to rinse the joint with water to remove any remaining flux.

Areas of use

The possibility of soldering with brass ensures a reliable connection of metal products, which determines the limits of application of this technology.

It would be impossible to do without this method of joining parts when producing products in such industries as:

• electronic manufacturing;
• assembly of refrigeration and heat exchange equipment (in this case, brass solder is used when soldering thin copper tubes);
• production of special cutting tools (cutters and attachments for them).

In the electronics industry, brass solders can be used to solder components of complex circuits and connect them to metal conductors.

In addition, brass solders are widely used when it is necessary to join metal workpieces of different thicknesses, as well as when carrying out tinning operations, which ensure the creation of a reliable protective coating on the metal surface.

Three technologies

There are three technologies for soldering iron with tin:

1. soldering iron To do this, you will have to use soft solders with a high lead content;
2. blowtorch. This will require hard solders with a high tin content;
3. electrical soldering of iron.

The first method is used if the iron will not be subjected to heavy loads during operation. The second is tinning of iron with tin, when tin solder is applied to the surface of a metal product and rubbed over its entire plane in a thin layer.

This technology requires soldering flux. The third option is used on a production scale, for which special equipment is used.

Carbide soldering. Brazing of carbide plates.

SOLDERING IN FLAME, GAS OR ELECTRIC OVEN.

Preheating of the rod.

The cutter head is slowly heated to the melting point of borax

Preparing the cutter for soldering.

The heated nest is sprinkled with borax, then the cutter is removed from the furnace and the resulting liquid layer of slag on the nest is cleaned with a metal brush.

Then the nest is again sprinkled with borax, after which a hard alloy plate is installed in it, the appropriate amount of solder is placed on top and again sprinkled with borax, so that the borax covers the solder and the entire plate with a continuous layer.

This operation must be performed quickly so that the rod does not have time to cool.

Solder melting.

The head of the cutter prepared for soldering is placed in the oven window at a temperature of 1200° and held until the solder melts.

Record clamp.

As soon as the solder melts and flows under the plate, the cutter is quickly removed from the oven, placed on a stand, the plate is straightened in the socket with a pointed rod and pressed tightly against the supporting surfaces of the socket. The pressure lasts a few seconds until the solder hardens.

Cooling of the cutter.

To avoid sudden cooling, leading to the appearance of cracks in the carbide plate, the cutter is placed in a box with charcoal grains or dry heated sand, where the cutter slowly cools.

It is much better to place the cutters, immediately after soldering, in a chamber oven heated to a temperature of 250°. The cutters are kept in the oven for 5-6 hours, after which they are cooled along with the oven.

Cleaning the cutter.

After soldering, the cutter is cleaned of scale using a sandblasting machine.

CONTACT SOLDERING ON ELECTRIC WELDING MACHINES.

Contact soldering is carried out on butt electric welding machines, which are equipped with a simple device consisting of 2 flat contact jaws, a set of end contacts, a block with a weight and a pedal button to the contactor of the device. The contact is made 2-3 mm below the carbide plate.

The soldering operation is very similar to the furnace operation and consists of the following:

1. The cutter rod is clamped in the contact jaws in such a way as to ensure the largest possible contact surface of the cutter end with the end contact surface.

2.The end contact is brought in and pressed against the rod.

3. The socket for the plate is sprinkled with borax, and then, by periodically turning the current on and off, the cutter head is heated to the melting point of the borax (800°).
After the borax has melted, use a metal brush to clean the nest from oxides and slags and sprinkle it again with borax; a hard alloy plate is placed on top, solder is placed on top of it, and borax is again thickly sprinkled on top. RIGHT .
The contact does not touch the carbide plate INCORRECTLY . The contact touches the carbide plate.

4.The current is turned on to melt the solder, after which the current is turned off, and the plate is pressed to the socket with a pointed metal rod.

5. The cutter is released from the clamps and placed in a box with charcoal grains or dry heated sand for slow cooling.

6. The cooling cutter is cleaned of scale using a sandblasting machine.

GAS SOCKET

In this method, the heat source is an oxygen-acetylene burner. It should be noted that this method is used only in the absence of other heat sources described above, or when it is necessary to solder a small number of tools.

The carbide insert is heated by a flame directed at the cutter shaft. The burner flame must contain a large amount of acetylene.

The soldering process is similar to the furnace process described above.

Soldering by this method should be entrusted to a welder with sufficient experience.

With any soldering method, as a result, solder in the form of a thin (up to 0.1 mm) continuous film must connect all contact surfaces of the plate and socket.

How to solder will win?

How to solder will win?
Guys, please tell me how to solder the win at home? And what is needed for this, maybe someone knows.

9 (or more) years ago Posts: 91

Re: How to solder will win?

Solder with brass, sprinkle with borax. Everything is there, look on the forum, everything has been discussed many times..

Peace and love to you, kind person.

11 (or more) years ago Posts: 3,094

Re: How to solder will win?

LexaLexa Writes: ——————————————————- > Solder with brass, sprinkle > with borax. Everything is there, look on > the forum, everything has been > discussed many times..

Maybe you can give me a link, otherwise I also asked myself this question. I searched all over the Internet but found nothing.

9 (or more) years ago Posts: 442

Re: How to solder will win?

Do you want to radically change your life? Just don't pay for the Internet!

11 (or more) years ago Posts: 1,185

Re: How to solder will win?

When they were soldering, I stood next to me - they heated it red-hot with an autogen, sprinkled it with borax and melted a brass strip under the flame of a burner. Well, clean the soldering area first. something like this

10 (or more) years ago Posts: 2,456

Re: How to solder will win?

usa Writes: > I was standing next to me when they were soldering > If possible, more step-by-step information. And how thick is the winning plate needed? I have 5mm, is that enough?

9 (or more) years ago Posts: 91

Re: How to solder will win?

For soldering you need oxygen and a propane torch. thoroughly clean the soldering area. Then you place the solder next to it and begin to warm up the metal first and alternately sprinkle the solder with plenty of borax. heating the metal to a carrot color, tinning with solder and moving the soldering and soldering, do not forget to sprinkle with borax. And do not allow the brass to shoot. It's a borax shortage. Once the seams are filled with solder, warm up the soldering area until it is a uniform carrot color. don't forget to sprinkle in borax. that's all.

8 (or more) years ago Posts: 853

Brazing

The use of hard solders occupies an intermediate position between low-temperature soldering and welding.

Hard soldering diagram.

They are used in cases where the strength of the resulting joints and the integrity of the metal structure become important. In this process, carbide plates are often used, which, when connected, do not spoil the original geometry of the structure.

This technology is used for repairing refrigeration or heat exchange systems, steel or copper pipelines, etc. It is also used in automotive repair to repair radiators, engines, transmissions, bodies and other similar parts.

If there is a need to repair products that are susceptible to high temperatures during operation (for example, a wood-burning samovar), then high-temperature soldering is simply necessary.

As for the equipment, in this case, a technique is required that is capable of providing a temperature higher than that required for melting the parts being connected. The average range can vary from 450 to 1200 degrees, provided that the entire procedure is performed at home. Gas burners, inductors and furnaces have such indicators.

Soldering at home

Soldering cutters is a necessary procedure that is periodically required in turning.
In order to solder carbide plates onto the holders of turning tools, to carry out local hardening of the tool, and hard soldering of small parts, heating with high-frequency currents or a gas burner flame is used. Despite the fact that HDTV equipment shows excellent results when soldering these elements, it is quite bulky and expensive, which makes it practically inaccessible for working at home. Regarding the gas torch, it should be used mostly by professional welders in accordance with all the necessary rules.

How to solder cutters yourself?

In order to perform soldering, you must follow the following steps:

1. First of all, it is necessary to clean all metal elements. The oxide film is removed.
2. The cutter holder is installed on the transformer busbars. The area that will be solderable must be pre-treated with flux. After this, the solder begins to work.
3. Using tweezers, solder is inserted between the edges that require joining. In a particular case, it is better to use a sheet of brass for this purpose.
4. During operation of the unit, the contact area will heat up. This contributes to the melting of the metal, and as soon as this process is completed, the contact will disintegrate, and, accordingly, the process will stop. Therefore, in order for soldering to be continuous, all work is carried out in pulse mode, while the load on the windings must be applied gradually.

The heating itself is carried out over the entire surface, moving smoothly from side to side. The solder should acquire a color from dark cherry to light cherry, which will indicate heating to the required temperature.

While visually monitoring the entire process, it is necessary to carefully apply all the solder. You should know that the holder heats up at a rate of 80-100 degrees per second. Using this method for connecting cutters, you can be sure of obtaining excellent quality.

If the flux has been applied in sufficient quantity, the solder will spread easily. After completion of the work, the seams are cleaned.

It is believed that a high-grade connection is one that does not exceed 0.1 mm. As is clear, there is nothing complicated in home soldering. The main thing is to have all the necessary tools and materials at hand. But you need to remember that during the entire process you should follow personal safety rules, since high temperatures can harm the solder.

Forgotten way

However, another method of processing cutters by heating has survived to this day, which we all began to forget - soldering on contact machines. This method is optimal for processing parts at home.

Design features and principle of operation

The principle of implementation of the method is the thermal effect of electric current on the conductor. Moreover, the amount of heat generated during work at home depends on the magnitude of the electric current, the electrical resistance of the conductor, as well as the time of its exposure to the conductor.

Based on this dependence, a special device was created, which is a step-down transformer. Thanks to this device, it becomes possible to solder the elements in question, recreate a high-quality part, etc. The primary winding of the transformer is designed for 220 V, and the secondary winding for 2 V. The cross-section of the magnetic circuit is 50 square centimeters. The transformer is fixed to the base, while the contact bars of the secondary winding of the device are located on the insulating gasket.

The base of the transformer is made of sheet steel, the thickness of which is 5 centimeters. The legs are screwed into the base from below. The base is also equipped with two windows, representing two ventilations (purpose: exit of bolts fastening the contact bus to the textolite insulator). It is worth noting that the holes located along the edges of the insulator serve to attach it to the base.

The ends of the secondary winding of the device are inserted into the holes of the clamps. The transformer is protected by a casing and is also attached to the base with corners. An insulating block is fitted to one of the corners.

Carbide soldering. Brazing of carbide plates.

SOLDERING IN FLAME, GAS OR ELECTRIC OVEN.

Preheating of the rod.

The cutter head is slowly heated to the melting point of borax

Preparing the cutter for soldering.

The heated nest is sprinkled with borax, then the cutter is removed from the furnace and the resulting liquid layer of slag on the nest is cleaned with a metal brush.

Then the nest is again sprinkled with borax, after which a hard alloy plate is installed in it, the appropriate amount of solder is placed on top and again sprinkled with borax, so that the borax covers the solder and the entire plate with a continuous layer.

This operation must be performed quickly so that the rod does not have time to cool.

Solder melting.

The head of the cutter prepared for soldering is placed in the oven window at a temperature of 1200° and held until the solder melts.

Record clamp.

As soon as the solder melts and flows under the plate, the cutter is quickly removed from the oven, placed on a stand, the plate is straightened in the socket with a pointed rod and pressed tightly against the supporting surfaces of the socket. The pressure lasts a few seconds until the solder hardens.

Safety precautions

Soldering iron with tin is an unsafe process. Therefore, precautions must be strictly observed. Protective gloves are put on your hands, and a stand must be installed under the soldering iron so that the heated tip does not touch the table and available materials. And the procedure itself must be carried out carefully.

Despite the apparent simplicity of the soldering operation, it is actually a serious procedure. And you need to treat it with great attention. Something was missed, they were even applied incorrectly, and we can assume that the quality of the joint has dropped sharply. Therefore, it is important to approach each stage responsibly, especially when it comes to cleaning two joined iron products.

Recommended types of solder

The following alloys are most often used as solder:

1. Copper-nickel, which can withstand operating temperatures up to 900 degrees Celsius. It is used in the manufacture of tools designed for increased loads.
2. Electrolytic copper has also become widespread. Heating of the cutting part of the tool in this case can reach a temperature of 700 degrees Celsius.
3. Brass-nickel compositions are similar to the previous solder, but are slightly cheaper.
4. Brass is designed for use under medium loads and heating the cutting edge up to 600 degrees Celsius.

To remove oxides and reduce the likelihood of metal oxidation, a flux, such as borax, is used.

Features of the solder used

The carbide plate soldered during processing takes the main load. That is why special attention is paid to solder. The melting point of the material used should be 300 degrees Celsius higher than the expected heating temperature of the tool during machining of the workpiece. In addition, the following criteria apply to solder:

1. High strength and elasticity. These qualities must be maintained when the temperature increases during processing of the workpiece.
2. Good fluidity ensures reliable connection of the plate to the base. In the production of cutters and milling cutters, attention is paid to the fact that the alloy must be evenly distributed over the entire base area.
3. Increased thermal conductivity. In order for the soldering to last a long time, it should not heat up during operation. The alloy used removes some of the heat, thereby increasing the service life of the cutting edge.

After wear of the carbide plates, it is possible to replace them. Due to this, the main part of the tool can be reused if there are no defects.

Solders and fluxes

For high-quality bonding, you need to be smart about the choice of flux and solder. This matters when the work is performed either with a gas torch or a soldering iron. Experienced craftsmen argue that it is necessary to use a more active solder, which contains zinc chloride. It is he who is able to clean the surface of objects from the appearing films of zinc oxide during heating.

Therefore, it is better to purchase a special flux, which can be borax. If you have to work with an alloy containing a large amount of copper, then it is better to use silver or copper-phosphorus components.

When the objects being joined differ in the material of manufacture, it is especially important to know which solder is suitable. Solder for soldering brass must be compatible with the surfaces of the products and have a temperature significantly lower. If there are no strict requirements for strength and appearance, the connection is possible with tin.

How to solder steel parts

Often there is a need to fasten steel parts without drilling and without welding. Soldering steel will help. But how to do it correctly, because there are special nuances here. A few recommendations from experts.

What kind of steel solders well?

Some grades of steel lend themselves well to soldering, while others are soldered with great difficulty and do not want to be combined with any solder or with any flux. As a rule, soft steels "for nails" are easy to solder. At the everyday level, this can also be explained by the fact that the material is dotted with microscopic craters and irregularities. But there are also electrical grades that are especially hard and elastic, and are used for shafts and precision mechanics. It depends on your luck here...

The question is that it is impossible for a home craftsman to determine the brand by eye. You can only find out how well a given part made of steel, or an alloy close to it, is soldered by experimentation.

How to make a tin connection - procedure

It all depends on how successfully the part can be tinned and how strong the contact of the tin solder with the steel is. In order for the contact to be satisfactory, if possible at all, the following must be done:

steel stripping, chemical stripping under solder;

Cleaning the steel is first done mechanically, using sandpaper, to remove layers of rust and dirt. Then a composition that reacts well with iron oxides is used as a flux.

The most harmless to use, but effective in this case, is orthophosphoric acid, which can be easily purchased at a car store as a “rust cleaner.”

The required power of heating devices depends entirely on the mass of the parts.

The process of soldering two steel parts

If you need to solder two large nails, then the power of one soldering iron 100 W will not be enough. To heat up a large nail or a similar weight steel part clamped in a vice, you need to use a hair dryer. Or a gas burner.

You will also need cotton wool on a stick to supply flux to the heating zone, and a soldering iron of 50 W or more.

The sanded steel is heated with a burner.

As a rule, steel parts that can be soldered develop a very strong bond with tin, i.e. When the metal is coated, it is tinned.

The same is repeated with another detail. Then the two parts located together are heated, and additional solder is applied to the contact area with a soldering iron.

How strong is the soldering of steel, can it be made stronger?

The strength of such a connection will be determined by many factors:

strength of bond between solder and metal,

But in any case, the strength of tin soldering cannot be compared with what is commonly understood as the strength characteristic of steel or “metal welding”.

You can strengthen it by using another solder - special strong and more refractory compounds containing silver, zinc, copper, etc.

Another direction for increasing strength is to cover with solder not only the plane, but also the sidewalls of the part - covering the part with solder. Then the pull-off resistance under multidirectional loads will be greater.

Extra strong soldering, special solders

To use compounds that provide a strong connection with steel, with its own melting point of about 800 - 900 degrees, you need to use a graphite crucible.

The work should only be carried out by specialists in metal smelting. It is necessary to know the basics of metal melting, the procedure for handling melts and safety precautions. In general, soldering of steel with heavy-duty solders is performed at specialized enterprises.

Possible solder composition:

• 55% zinc, 45% copper, some silicon to increase fluidity.

The composition is melted under a layer of coal in a graphite crucible. Steel parts to be soldered are heated with a gas burner. Phosphoric acid is used as a flux. The melt is fed to the parts. As a rule, tinning and soldering are carried out during one heating of both the parts and the solder. But such soldering of steel is more complex than simple welding...

Features of copper soldering

When soldering copper tubes, you can use both regular copper-phosphorus solder and those containing silver. The result is approximately the same, the quality of the seam is good.

Before starting soldering, the surface of the copper will need to be well heated with a gas burner, and only then apply solder. Otherwise, the quality of the seam may be unsatisfactory.

Some differences between these two solders can be noticed directly during the soldering process. For example, ordinary copper-phosphorus solder flows better, but solder with silver is no longer as flowable.

Sequence of work

1. The cutter holder is located on the tires of the device. Next comes the solder.
2. Solder is placed between the surfaces to be joined (using tweezers). In this case, the solder is a sheet of brass.
3. When the transformer is turned on, the contact area heats up, thereby causing the metal to melt, after which the contact is broken, and, as a result, the contact stops. Prevention of this is as follows: work should be carried out in intermittent mode, the load is smoothly applied to the windings using LATR.

The solder is applied carefully, the work is monitored exclusively visually. The heating rate of the holder during the soldering process is 80-100 g/sec. Soldering cutters using this method gives excellent results. A high-quality connection should not exceed 0.1 millimeters. Thanks to the device, such work becomes possible at home.

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