Carbon Tungsten Introduction of Wearable Steel Product (WCSP)

In the development and industrial production, a lot of important equipment and the spare parts work in the adverse conditions. For example, for the metal parts worked in the condition of high speed, high temperature, high pressure and heavy loading, the destroying in the form of abrasion, cauterization, oxidation and so on will aggravate. Thus, the wearability is one of the limits in developing the production and reducing the cost. According to the authoritative statistics, among the disabled metal mechanical accessories and parts, 75% of them are the abrasion of metal. Besides, the abrasion of metal would also decrease the running efficiency of mechanical equipment. To change the work-pieces or to repair frequently will increase the consumption of energy. The destroying of iron and steel because of friction and abrasion usually begins from the surface. So taking the protective ways to delay and control the surface destroying is the efficient method to solve the problem of abrasion, which promotes the generating of various technologies on surface anti-abrasion engineering, and makes the technologies of cladding, hot diffusion coating, hot spray painting, welding, membrane plating, high-energy beam and others develop rapidly. The surface wearable materials made with the above technologies, permanganate, high chromium, rare-earth wearable cast iron (steel), cast stone, stickup ceramic and other wearable materials make up a big family of wearable materials. Now, they all have their own merits. Each shows its special prowess and helps to developing the science & technology and the industrial production. However, each has its own shortages. The cast iron (cast steel) has the basic capability of cast iron typed products, but the hardness, intensity and toughness are quite weak, and the wearability is not enough. The cast-stone materials have a certain wearability, and the price is comparatively low, while they are too heavy. Besides, their anti-striking capability is a little bit weak. It’s easy to happen the accidents because of the destroyed inside stress. And you can’t cut or weld them at the spot when installing and repairing; The hard face of wearable layer formed by hot spray painting, welding or stickup ceramic has the good wearability and wide application scope. But the combining intensity with matrix is a little weak so that it’s easy to lose the function of anti-abrasion because of the dropped wearable layer; Wearable plating membrane’s and high-energy beam’s wearable layer can be used widely. But the wearable layer is too thin and the expense is too high. In the above circumstances, many users of wearable materials do hope to research and manufacture a kind of advanced but economic wearable material. Their technical requirements have been concluded into five items: The wearability of new wearable material has to be greatly better than the general one; The new wearable material has to be light but not too thin; The new wearable material has to have the merits of high intensity, hardness, toughness and anti-tire capacity; The new wearable material’s wearable layer can drop or crack when use so as to prevent the invalidation of anti-abrasion; The price of the new wearable material has to be widely accepted in the engineering industry. Among the present wearable materials, the one that can meet all the above requirements is few. However, WCSP can do it: The wearability of WCSP is high, usually 4-15 times higher than hardening tool steel; The thickness of WCSP matrix can change between 8-20mm according to users’ requirement. The thickness of wearable layer between 1-2mm can make WCSP work in the hard-abrasion conditions for a long time; WCSP is hard outside while tough inside. It has the merits of high hardness, intensity, toughness and anti-tire capacity; The main wearable layer is combined with steel matrix by metallurgy, which has the gradient changing without macro-interface so that it won’t drop or crack when use, especially in the working conditions with impulse abrasion; The capability price ratio of WCSP is high. Therefore, WCSP is warmly welcomed in the industries of metallurgy, electric power, building materials, petroleum, coal, chemical engineering, mechanism, light engineering and others as soon as it appears in the market. WCSP has been confirmed by the National Economic & Business Commission as “the National Advanced Products”. The manufacturing technique of WCSP has been applied for the national invention patent. This technology has passed the provincial appraising organized by the Science & Technology Department of Jiangsu Province, the checking and accepting of new-product by the Economic & Business Commission of Jiangsu Province.

WCSP has the wonderful comprehensive capability. Especially it’s really wearable. Thus, it’s suitable for various mechanical and electrical products that work in the hard conditions. They mainly are the products in the industries of metallurgy, building materials, electric power, petroleum, coal, chemical engineering, mechanism, light industry and so on. In the past, they failed to find the satisfactory wearable materials in the places with hard abrasion. So they only have to reduce their standards, and use a number of common materials to solve the problem of quality. The shortest use life of these common materials is only several hours. Even the longest use life will not more than 1-2 years. But after using WCSP instead of the original wearable parts of these mechanical and electrical products, the use life is several times or tens times longer than before. The result surprises and satisfies the users greatly. In the black and nonferrous metallurgy industry, for the wearable parts used in mining excavating, mining selecting, mining transport and other systems, the wearable parts used in sintering and smelting system, the rollers in the pressure processing and the wearable parts in the guiding system, after using WCSP instead of the above ones, they got the satisfactory effects. For example, a sintering sub-factory of a steel & iron company has chosen WCSP as the wearable material of 400m2 sintering machine system. After using it, the use life has improved 4-20 times; the economic benefits have improved 3-16 times. A rolling mill changed to use WCSP instead of the original rollers, guiding rollers and guiding boards of the rapid wire rolling mill. The use life is 2-4 times longer than the imported one. In the large-sized cement groups, WCSP is used in vertical grinder, powder-selecting machine, burner and duct catcher, the hopper & the slipping channel and the roller in material transport. The wearable result is convincing. For example, there are several domestic cement enterprises with the yearly output of 2,000,000 tons. The vertical grinders used by them are mainly imported form Denmark. The pull rods, protection boards and other parts of vertical grinders were welded the WC wearable layer about 8-10mm thick in the past, while the use life was no more than 4 months. After changing to use WCSP, they can still work over 2 years later.

If WCSP is used in anti-abrasion pieces, burners, coal-grinding machines, slag-classifying machines, powder cleaners, dust catchers, vans, different-typed pipes, gate valve and other equipment of the thermal power plant, the use life of equipment will increase greatly. Such as, in a power plant, after changing to use WCSP instead of the original anti-abrasion board of flue, the use life has increased over 5 times; in another power plant, after changing to use WCSP instead of the original anti-abrasion board for water-film dust catching, the use life has increased 8 times longer than the imported one; in a power factory, because the flowing speed is quite high, the use life of bent pipe for dust catching is very short, after using WCSP, the use life has improved over 15 times.

In the industries of petroleum, coal, chemical engineering, mechanisms, light engineering and so on, after changing to use WCSP instead of the original anti-abrasion accessories and parts with short use life for a period, the users all think that WCSP has wonderful wearablity and that it’s worthy of spreading greatly.

　 WCSP permeate WC into the steel matrix by using high-energy ion. Its surface has the special organization that forms the WC rich-collective layer with very high wearability. WC is a kind of highly hard ceramic materials. It’s hard as well as fragile. Except being used as skiving material, it’s seldom used directly. In 1920s, the scientists invented WC hard alloy, used as cutting tools, molding tools, measuring tools and drilling tools. Their wearability is 15-20 times more than speed-steel, which has achieved the first revolution of tools. When other industries decided to select the hard alloy of wolfram carbide as the wearable materials, they found the hard alloy made with the method of power metallurgy needs special pressing machines and sintering furnaces, which means it’s impossible to manufacture the accessories and parts with big sizes and complex shapes expected by the engineering industries. In addition, the wearability of hard alloy is quite high, but the toughness is comparatively weak. And it has the high brittleness and price. Because of the above reasons, the hard alloy has been only well used in the cutting tools, molding tools, measuring tools and drilling tools, while seldom been used in other mechanical & electrical products. In order to apply the hard alloy to other mechanical & electrical products, the carbonized tungsten welding technology has been invented, which has partly settled down the difficult problem of anti-abrasion in the surface of accessories and parts with complex shapes. We take the lead in using high-energy ion plating technology at home and abroad. Now, we can permeate WC into the steel matrix of complex-shaped accessories and parts. The WC rich-collective layer with high wearability is 0.3-0.5mm. The WC hardening layer is 1-1.5mm. This kind of products has the merits of high hardness, high intensity, high toughness, and excellent wearability. It’s the important development of steel’s surface changing technology and the surface changing technology of mechanical accessories and parts, which fills in the gaps of materials with hard surface at home and abroad, and takes the advanced position in the world.

The low-times metallographic organization of WCSP The SEM shape of micro-organization of WCSP

I, WCSP have the excellent comprehensive mechanics capability and comparatively high wearability: When WC is permeated into the steel matrix; it will form the metallurgy combination. Their respective consistency will have the gradient changing without macro-interface, which forms the special organization construction. Please find the micro organizing details in View 1 and View 2. Thus, the merits of WC and the merits of steel matrix are complementary. The surface of WCSP has the high hardness and wearability of WC. Even its anti-drawing capacity and anti-tire capacity are greatly improved compared with steel matrix. While the heart part still remains the high hardness and toughness of selected steel matrix. Between the surface and the heart part, there is an area of transition that the capacity changes gradually, which can effectively avoid the damage of materials happened when the capacity changes suddenly. The hardness of surface can change between HRC45-64 according to the users’ concrete requirements and the capabilities of selected steel matrix. The hardness of WCSP is not the unique standard of its wearability. WC in the soft matrix has the same wearability, which is only little worse than the wearability in the hard matrix. The distributing details of hardness from inside to outside are showed in View 3. In the metallurgy, electric power, building materials and other industries with various serious abrasion working conditions, although the thickness of wolfram carbide hardening layer in WCSP is only between 1-1.5mm, WCSP can perform very well with excellent comprehensive mechanics capability and high wearability, the use life is 3-10 times longer than the original wearable materials, some are even over 20 times longer. A number of practice have improved that WCSP has high wearability. However, the research of theory falls behind the practice. At present, the theories of metal and anti-abrasion fail to satisfactorily explain why WCSP has such high wearability. It needs the further theoretic research.

II, WCSP has high red hardness and hot hardness: For the equipment worked in 400-8000C in the metallurgy, electric power, cement and other industries, they needs comparatively high wearability as well as certain anti-hotness capability. If WCSP works in the temperature less than 8000C, it not only has excellent anti-hotness capability, but also has high hardness and satisfactory wearability. In order to improve its capabilities of anti-hotness and anti-abrasion, we can permeate other elements that can improve the capability of anti-hotness when permeating WC, so that it can imcrease the anti-oxidation capability as well as.

There are three kinds of supplying modes for WCSP: The first is that the users take the accessories by themselves, and we will permeate WC for them; The second is the users offer us the technical information of the needed anti-abrasion accessories and parts, we will take charge of the whole manufacture; The third one is we can manufacture the combined equipment of wearable work pieces and non wearable work pieces. The choice of the above is up to the users.

Different supplying modes have different price calculating methods. If you choose the first one, we will only charge the permeating fee; If you choose the second one, we will charge the raw material fee, the mechanical processing fee and plating fee; If you choose the third one, we will charge the same fee as the second kind for permeating WC wearable work pieces, while charge the non wearable work pieces as entrusted processing.

Whichever price calculating method we choose, the plating fee is made up of the fee of permeated area (M2) and the added fee of overweight. The added fee of overweight is the one formed because the plating area of accessories and parts is small, but they are very heavy, and when permeating, the using ratio of furnace is lower, the electricity fee is higher, the wasting materials are more. Usually, if the weight of per m2 (the plating area) is within 100 kg (including 100 kg) heavy, we won’t charge the added overweight fee. For the overweight part (more than 100kg), we will charge the added overweight fee based on the excessive weight.

In the family of high-energy ion permeating functionally gradient products, except WCSP, there still are many other products with special functions, such as anti-hotness & anti-abrasion products, anti-hotness & anti-erosion products, anti-abrasion & anti-erosion products, and the products that can improve the light, electric and magnetic capability and so on. Their special capability are all subject to the advanced characteristics of the high-energy ion permeating technology.

The components of the high-energy ion-permeating layer can be controlled. The permeating layer is sealed without any perforation. Thus, we can permeate the anti-erosion media—metal, alloy or nonmetal with the function of “anti-erosion” into the ceramic steel matrix or anti-erosion alloy matrix, so as to form the special stainless steel or special alloy in the surface of matrix, which can satisfy the special requirements to anti-erosion materials in the various working conditions.

To permeate the needed alloy or nonmetal into the anti-hot steel matrix or high-temperature alloy matrix will not be limited by the thermodynamic conditions, which can’t be obtained by using the common smelting methods. The alloy and metal compounds gotten in this way has the better high temperature mechanical capability than matrix materials. They have the better anti-hot & anti-oxidation permeate layer. Thus, they can meet the special requirements to the wearable materials in the various high temperatures working conditions.

Through the high-energy ion permeating technology, we can permeate excessive Si or other metal elements on the common Si steel slice so as to improve its electromagnetic capability greatly. Between the materials that are hard to weld, we permeate the easy-welding elements so as to ameliorate the welding capability and improve the welding quality.

The high-energy ion permeating technology is a new and advanced technology that has developed greatly in the past several years. It is a new branch in the field of surface engineering. We sincerely hope to work with the colleagues devoting into the high-energy ion permeating technology to strengthen the research of theories, emphasize the practical application, and make the future of the high-energy ion permeating technology more splendid.