SLD material | AsiaVest steel mold (certified) | Jiangmen, Dongguan City An Yongwei SLD provided by steel mold shop. Dongguan City An Yongwei mold steel shop (www.dgyongwei.com) is specialized in the "mold steel, DC53, SKD11.SUS440C, SUS420" business, the company adhering to the "honesty, hard service" concept, to provide you with the most quality products and services. Welcome to inquire! Contact: Simon / R. Heat in thermal shock conditions serving as a mold, forging hundreds or thousands of times SLD materials, many of the small-groove surface cracks appear, the shape of a mesh, radial, parallel shape. These cracks are generally only a few millimeters deep, does not extend to depth. Such as forging die during service, contact the hot-groove surface rough, its surface temperature to rise rapidly heated 4007000C, while the inner layer is still at a relatively low temperature. But subject to the heat expansion of the surface of the inner constraints, resulting in compressive stress in the surface layer SLD material, forgings after demolding, since the mold surface is sprayed a coolant and a lubricant, so that the surface has dropped to 150-200 ℃ and contraction, when the surface contraction also restricted the inner, they produce back to the stress, so-groove in the surface layer of metal to produce tensile stress, because the role of alternating compressive stress is caused by thermal fatigue of the underlying causes. Plus the high temperature oxidation, friction coolants and lubricants as well as deformation of the metal electrochemical corrosion, more accelerated thermal fatigue process. Thus, thermal fatigue process is extremely complex physical and chemical processes. Die wear resistance of steel depends not only on its hardness, but also depends on the nature, size, distribution and abundance of its carbides. In the mold steel SLD, currently at high speed steel and high-carbon high-chromium steel highest wear resistance. But in the case of steel, the presence of severe carbide segregation or large carbide particles, these carbides easy to peel off and cause abrasive wear, more so wear light-load speed up the cold mold (sheet blanking, drawing, bending etc.) of the impact load is not primarily static wear. Under static wear conditions, the carbon content of the steel mold more, higher wear resistance. In impact wear conditions (such as cold heading, cold extrusion, forging, etc.), excessive mold steel carbide help to improve the wear resistance, but because of the impact of abrasive wear will reduce its wear resistance. Studies have shown that, under the impact of abrasive wear conditions, the carbon content of the steel mold with 6 00 / a ceiling, above which the wear process dramatically accelerated. Impact loading shovel die in cold working conditions, such as excessive carbide steel mold, easy to wear due to the impact of the emergence of flaking. These hard particles flaking, will become abrasive and accelerate the wear rate. Hot surfaces of the mold cavity, reducing wear due to high temperature softening leaving. In addition, iron oxide skin also play a role in the abrasive, while there are high-temperature oxidation corrosion. Therefore, the wear process is extremely complex hot die wear much faster than the cold mold.