Mold cryogenic treatment
Mould cryogenic treatment: cryogenic environment is mainly refers to material handling needs - 190 ° C to 230 ° C temperature. (non-liquid nitrogen medium-temperature refrigeration whole computer)
Applicable materials: all metallic or non-metallic materials, such as alloys, carbides, plastics (nylon and teflon), aluminum and ceramics.
Cryogenic technology: when the dissolution and diffusion of the alloy and carbon produced in the heat treatment process of metals and refractory metals combine with the formation of austenite (austenite), the formation of martensite (martensite) is inhibited during the cooling process due to low temperature generation and due to the final transition. For example, point martensite (Mf) is very low,
Such as: W18Cr4V (high speed tool steel) of intermediate frequency point - more than 190 ° C, cool to room temperature and quenching, therefore a large amount of residual austenite experience reduce the hardness, wear resistance and service life of metal, and because the austenite high brittle fracture easily cause metal, and there are many physical properties, E thermal and magnetic decline in particular.
Because the austenite is very strong at low temperature and decomposes, the original defect (porosity and stress concentration part) becomes plastic flow structure refinement, as long as the metal is placed in the low temperature environment, the austenite becomes martensite, thus eliminating the stress.
At ultra-low temperature, due to the shrinkage of tissue volume, the reduction of iron lattice constant and the precipitation of carbon atoms, the driving force is strengthened, so that a large amount of martensite precipitates out of the matrix, and these ultra-fine crystals will improve the strength of the material, as well as increase the wear resistance and rigidity.
Ultra-low temperature metal atoms can transfer transport capacity, so that they can not be separated, so that the diffusion between the atoms bond more closely.