Wear-resistant Castings for heat treatment
As the purpose of Wear-resistant Castings, heat treatment is very much, the basic can be divided into two categories, the first is the structure of the organization will not change through heat treatment or should not be changed, the second is the basic organizational structure changes The The first heat treatment program is mainly used to eliminate the internal stress, and this stress in the stainless steel casting process due to cooling conditions and conditions caused by different. Organization, strength and other mechanical properties, not due to heat treatment and significant changes.
For the second type of heat treatment and the main base organizations have undergone significant changes can be broadly divided into five categories:
1, softening annealing: its main purpose is to break down the carbide, its hardness is reduced, and improve the processing performance, for ductile iron, the purpose is to get more ferrite.
2, normalizing treatment: the main purpose is to obtain pearlite and sorbite to improve the mechanical properties of stainless steel casting.
3, quenching: mainly in order to obtain a higher hardness or wear strength, while the very high surface wear characteristics.
4, the surface hardening treatment: mainly to obtain the surface hardened layer, while the very high surface wear characteristics.
5, precipitation hardening treatment: mainly to obtain high strength and elongation does not occur so drastic changes.
Melt-resistant castings are made of fusible material made of fusible model, in which a number of layers of special refractory coating, after drying and hardening to form a whole shell, and then steam or hot water from the shell And then the mold shell in the sand box, filled with dry sand in its shape, and finally the mold into the roasting furnace after high temperature roasting, casting or shell by roasting, in which the molten metal casting And get cast.
The Wear-resistant Castings are made of precision, complex, close to the final shape of the parts, which can be used without any processing or very little processing. It is an advanced process of near net forming, which is an excellent process technology in the casting industry, Its application is very extensive. It is not only suitable for all types of casting of various alloys, but also to produce the casting size accuracy, surface quality than other casting methods to be high, and even other casting methods difficult to cast the complex, high temperature, easy to process the casting, Can be cast by wear-resistant casting cast.
At present, the world's investment in mold-casting process has developed rapidly and widely used. From the current situation, the future development trend of the process is that the casting products are getting closer to the parts and components. The traditional casting is only blank. Adapt to market quick response. Parts and components of the complexity and quality of the grade is getting higher and higher, more and more strong means of research and development, professional collaboration began to show, CAD, CAM, CAE application of parts and components to become the main technology.
From the current development situation analysis, investment casting technology is very wide range of applications, the future development prospects to be broad.