负压消失模工艺中EPS热解产物的研究

消失模铸造工艺中ＥＰＳ热解过程及热解产物的组成一直是消失模工艺研究的热点之一。采用气相色谱法对负压消失模工艺型腔中ＥＰＳ热解产物样品进行了分析，并且考察了合金浇注温度、负压度以及涂层透气性对解产物组成的影响，试验结果表明，浇注温度对ＥＰＳ热解产物的组成以及ＥＰＳ在型腔中的发气量有着决定性的影响，从而影响金属液流动前沿的形态；随着负压度和涂层透气必珠增加，ＥＰＳ热解产物能够更快地排出型腔，在高温区停

Study on the Thermal Degraded Products of EPS in the Lost Foam Casting Process

Thermal degraded product of EPS in mold cavity for the lost foam casting with vacuum were analyzed by gas chromatography. Effects of pouring temperature, vacuum rate and permeability of the coating layer on the components of thermal degraded products of EPS were investigated. The results showed that pouring temperature play a critical role on components of thermal degraded product of EPS and gas evolution in mold cavity, which has an effect on the front shape of the molten metal. With the increase of vacuum rate and permeability, the thermal degraded products of EPS remove from the mold cavity more quickly and stay in high temperature area shorter, so gas evolution decreases.