A dureza do tratamento térmico do molde é um índice de propriedade mecânica muito importante, e dureza não qualificada é um defeito muito sério. Dureza insuficiente ou dureza irregular após o tratamento térmico reduzirá a resistência ao desgaste e à fadiga do molde, lead to early failure of the mould, and seriously reduce the service life of the mould.
- Causas
1) The cross-section of the mould is large and the hardenability of the steel is poor. Por exemplo, the steel with low hardenability is selected for the large-scale mould.
2) Carbide segregation is serious or coarse in the original structure of die steel. Graphite carbon and carbide segregation and aggregation exist in the steel.
3) The forging process of the mould is incorrect, and no good spheroidizing annealing is carried out after forging, resulting in poor spheroidizing structure of the mould steel.
4) The decarburization layer on the surface of the mould is not removed by annealing or quenching heating.
5) Excessive quenching temperature and excessive retained austenite after quenching, or too low quenching temperature and insufficient heating and holding time make the phase transformation of mould steel incomplete.
6) After quenching and heating, the cooling speed of the mould is too slow, the grading and isothermal temperature are too high or the time is too long, and the selection of quenching cooling medium is inappropriate.
7) too little water in alkali bath or too much impurity in quenching cooling medium or aging of quenching cooling medium.
8) Temperature is too high and cooling is insufficient when the quenching cooling medium is released after quenching and cooling of the mould.
9) insufficient tempering and high tempering temperature.
- Countermeasures
1) Correct selection of mould steel, large-scale mould should choose high alloy mould steel with high hardenability.
2) Strengthen the inspection of raw materials to ensure that raw materials meet the standards. Reasonable forging and spheroidizing annealing are carried out on the steel with bad raw materials to ensure good structure. Carbon tool steels are not easily annealed many times to prevent graphitization.
3) Strict implementation of forging and spheroidizing annealing processes to ensure a good preparation of heat treatment structure.
4) Before heat treatment, rust spots and oxide scales on the surface of the mould should be thoroughly removed, and attention should be paid to the protection during heating. Vacuum heating quenching or protective atmosphere heating quenching should be adopted as far as possible, and good deoxidization treatment should be carried out when salt bath heating.
5) Correctly formulate the process parameters of quenching and heating of the die to ensure that the phase transformation is sufficient and the cooling speed is faster than the critical cooling speed to obtain qualified metallographic structure.
6) Correct selection of quenching medium and cooling mode, strict control of classification and isothermal temperature and time.
7) The water content of alkali bath should be strictly controlled. The quenching cooling medium used for a long time should be filtered and replaced regularly, and kept clean. The quenching cooling characteristic curve should be tested regularly.
8) For large-sized moulds, the time of immersion in quenching cooling medium should be prolonged to prevent the temperature of quenching cooling medium from being too high.
9) Depois de temperar, the mould should be tempered promptly and sufficiently, and the tempering temperature should be prevented from being too high.
10) The mould with high hardness requirement can be treated by cryogenic treatment (por exemplo. – 110 ~196 C).
11) Surface strengthening.
JasonMould Industrial Company Limited, estabelecida em 2010, é um líder fábrica de moldes da china. JasonMould é especialista na produção de moldes de plástico para eletrodomésticos, equipamentos médicos, equipamentos eletrônicos, equipamentos de segurança, bem como sistema de monitoramento.
A empresa acabou 15000 fábrica de metros quadrados. Com divisões de ferramentas de injeção de plástico possuindo diferentes maquinários e conhecimentos, JasonMould oferece ferramentas desde pequenas e precisas peças de telefones celulares até tão grandes quanto peças automotivas. Nossas ferramentas são exportadas principalmente para os EUA., Europa, Japão e Reino Unido. A estratégia de diversificação e serviço completo da JasonMould ganhou elogios de clientes em todo o mundo.
Nossa missão é fornecer aos nossos clientes produtos e serviços de moldagem de alta qualidade. Nosso objetivo é superar as expectativas de preços de nossos clientes, qualidade e entrega no prazo. Para cumprir nossa missão, JasonMould:
- Compromete-se a melhorar continuamente as habilidades e eficiência dos funcionários,
- Oferece aos nossos funcionários um ambiente de trabalho limpo e seguro,
- Atualiza a tecnologia da máquina e o equipamento de suporte por meio de um programa de manutenção rígido, e
- Mantém as ferramentas dos clientes em seu pico mais alto de desempenho
Para mais sobre Custo de moldagem por injeção da China,por favor visite https://www.jasonmolding.com/
Eles exportam suas ferramentas para diferentes partes do mundo e se tornaram um dos nomes mais famosos do setor industrial:
Pessoa de contato: James Yuan
Nome da empresa: JasonMould Industrial Company Limited
Endereço: LongGang Village,LongXi Town,BoLuo County,Cidade de HuiZhou,Província de Guangdong, China
Telefone: 86-752-6682869
E-mail: [email protected]
Local na rede Internet: https://www.jasonmolding.com
