On 2018-08-08 14:48:54
Requirements of heat treatment and the whole process
In Wuxi heat treatment process, first of all, reasonable materials should be selected. Take the mold as an example, for the mold with complex density, micro deformation abrasive steel with good quality should be selected; for the abrasive steel with severe carbide segregation, forging and tempering heat treatment should be carried out; for the larger or non forging abrasive steel, solution refining heat treatment should be carried out.
Secondly, the design of the mould should be reasonable and the shape should be symmetrical; the larger mould should have a good grasp of the law of deformation, and the machining allowance should be reserved; the large and complex mould can adopt the combined structure; and the pre heat treatment should be carried out. Of course, reasonable selection of heating temperature and control temperature is also very important for Wuxi heat treatment processing. Slow heating, preheating and other balanced heating methods can be adopted to reduce the deformation of mold heat treatment.
If conditions permit, vacuum heating quenching and deep cooling after quenching shall be adopted as far as possible. In addition, the correct heat treatment process operation and the reasonable tempering heat treatment process are also the limited measures to reduce the deformation of the precision and complex mold.
Secondly, if it is understood simply, Wuxi heat treatment process is a heating, heat preservation and cooling process, an important part of the mechanical industry, an indispensable and extremely important link in the production chain of modern manufacturing industry, a key processing process to promote the full potential of metal materials, improve the quality and service life of mechanical parts, and a basic technology of manufacturing industry.
For example, quenching is a heat treatment process in which the steel is heated to a certain temperature above the critical temperature of AC3 or AC1, kept for a period of time, all or part of it is austenitized, and then cooled to below ms at a faster cooling rate than the critical cooling rate for martensitic transformation. Tempering is a heat treatment process in which the quenched workpiece is heated to a proper temperature below the critical point AC1 for a certain period of time, and then cooled in a satisfactory way to obtain the required structure and properties.
Normalizing in Wuxi heat treatment process is to heat steel or steel parts to a proper temperature above the critical point AC3 or ACM for a certain period of time and then cool them in the air to obtain pearlite like structure. For annealing, it is necessary to heat the hypoeutectoid steel workpiece to 20-40 degrees above AC3, after holding for a period of time, cool it slowly with the furnace to 500 degrees below in air. In addition, there are many, including spheroidizing annealing, solution treatment, aging, quenching and tempering treatment.