Die life is related to many factors, including mold mold material selection, heat treatment process, structure design, mold machining, etc.
1, mold material selection
Mold material selection is one of the important factors affecting the service life of mould. So in the mold when select material should be combined with the performance of the mold itself and use function. For many cold die, should first consider the steel's strength, toughness and wear resistance. In terms of practical effect, strength, toughness and wear resistance of steel is inversely proportional relationship. Most of the time, mould will appear the phenomenon of brittle cracking, this time should choose strength but lower toughness better materials, can also be used as a special steel. Of course, also can choose high strength and toughness of the strong steel to make up the toughness is not strong. But if both good toughness and wear resistance, in addition to select a reasonable mold material, should also be treated surface, improve the processing performance, mirror such aspects as change mould wear resistance.
2, the structure design is reasonable
Generally speaking, the unreasonable structure of mould anomalies are early lead to mold deformation failure caused by the heat. On the design of the mould, the sharp and rounded cross section of avoid mostly, these are easy to cause the mould deformation and damage. But if the sharp corner cannot be stopped, should use a combination or put the fillet processing eventually to be replaced after heat treatment, so make up for the mistakes from the whole structure. In addition, the section area is uniformity is an important guarantee to prevent deformation and cracking of mould. In the same situation, a lot of complicated shape easy cracking of mould should be combined, reduce the influence of interface on the die life.
3, the influence of heat treatment
Most of the time, die early failure was caused by improper heat treatment. Heat treatment technology is not science and heat treatment quality is to make heat treatment to the mold has a harmful effect on the mission of the important performance. According to incomplete statistics, the improper heat treatment of die service life of the early failure of the phenomenon is a lot of, can reach almost 70%. Therefore, correct and reasonable heat treatment technology for the importance of the service life of the mold. Conversely, or improper heat treatment technology is not mature, etc, will be indirectly or directly harm the performance of the mould and integrity, great damage on the die life. Generally speaking, the performance of the heat treatment form mainly has: (1) quenching overheat. Much of the grain growth is caused by quenching overheat, leading to the toughness to bear ability, can make the mould are more likely to happen in the early fracture phenomenon. (2) the surface decarburization. Mold is typically after quenching and high temperature tempering, if protection measures do not reach the designated position, will make its surface decarburization. If not timely remove decarburization layer, so will greatly reduce the mould wear resistance, will shorten the life. (3) quenching cracks. Mould in the link of quenching, is prone to crack. Crack appears sure to reduce die of cold and hot fatigue life, moreover can cause earlier fracture, seriously affected the normal use of mould. (4) tempering. Due to various reasons, mould tempering link will appear error, cause mould insufficient tempering. Such residual quenching will be hold in the mold, the mold of the toughness, fracture occurred.
To sum up, the service life of mould and a lot of factors have relations, in selecting mould material, heat treatment, etc, to combine the service life of mould, various comprehensive choice. So to improve the service life of the mould, need to have professional and technical personnel in repeated experiment test to select the optimal processing technology, in order to improve the service life of the mold.
