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Taizhou Union Plastic Mould Co.,Ltd

ADD:No.26, MaoFeng Street, Beicheng Development Area, Huangyan Dist., Taizhou, Zhejiang, China

Post Code: 312080

Contact:Ms vicky






The Mold Hardness Is Not Enough How To Do ?
Aug 28, 2018

May be the cause of insufficient hardness or uneven: 1) the mold section, steel hardenability is poor, such as a large mold chose low hardenability of steel grade 2) steel carbide segregation in the original organization bulky, serious or organization in graphite carbon steel and carbide segregation gathered 3) die forging process is not correct, not good spheroidizing annealing after forging, steel spheroidizing tissues bad 4) mould surface to remove all annealing and quenching caused by heating of the decarburization layer 5) die quenching temperature is too high, the residual austenite after quenching size too much;Or quenching temperature is too low, heat preservation time is insufficient, the phase change of the die steel is not completely after 6) die quenching heating cooling speed too slow, classification and the isothermal temperature or time is too long, improper choice 7) alkali bath quenching cooling medium moisture too little, too much or quenching cooling medium containing impurities, or aging after 8) die quenching cooling quenching cooling medium when the quenching cooling medium temperature is exorbitant, insufficient cooling 9) insufficient tempering and tempering temperature too high for more than 9 point analysis, we find the corresponding solution of 1) the right to choose die steel, should choose high hardenability of large injection mould are high alloy steel2) to strengthen the inspection of raw materials and ensure raw materials meet the standard of bad raw materials reasonable forging steel and spheroidizing annealing treatment, ensure good organization carbon tool steel is not easy to annealing for many times, in case of graphitization 3) strict implementation of forging process and the spheroidizing annealing process, ensure good preparation before heat treatment group 4) heat treatment should be thoroughly remove rust stain on the surface of the mold and scale, and pay attention to the protection of the heating, as far as possible the quenching vacuum or protective atmosphere heating quenching, salt bath heating deoxidizing process should be good5) develop mould heating quenching process parameters correctly, to ensure that the phase change fully, at greater than the critical cooling rate of cooling speed for fast cooling, in order to obtain qualified microstructure 6) correct selection of quenching cooling medium and cooling mode, strictly control the classification and the isothermal temperature and time) to strictly control the alkali bath water content, the quenching cooling medium used for a long time to often filtered and replaced periodically, and keep it clean, tested periodically quenching and cooling characteristic curve of 8) the size of the mold, extend time of immersion quenching cooling medium and prevent mold out of the quenching cooling medium temperature is too high10) for molds with high hardness requirements, deep cooling treatment (such as -110~-196) 11) can be adopted for surface strengthening treatment