高刚度低应力床身的生产方法及精度研究

Manufacturing Methods and Accuracy Research of High Rigidity and Low Stress Lathe Bed

从炉料配比、化学成分、力学性能要求和熔炼工艺、孕育处理、时效处理等方面系统地介绍了高刚度低应力床身铸件HT300的生产工艺及其先进性。采用传统生产工艺和新工艺分别生产2组床身铸件,对比测量其理化指标和导轨面直线度。对比结果表明：高CE下,通过0.5%~0.7%Cu＋0.2%~0.3%Cr＋0.035%~0.05Sn复合合金化、低的打箱温度（≤280℃）和阶梯式升温降温法热时效,可获得高刚度低应力床身铸件HT300;与低CE高强度床身铸件相比,高CE高刚度低应力床身铸件的导轨面具有相对更小的变形量、更高的精度和精度保持性。

Production process and its advancement of high rigidity and low stress HT300 lathe bed casting were introduced from aspects of charge ratio,chemical composition,mechanical properties and melting process requirements,inoculation,aging,et al. Two sets of bed castings were produced by traditional production process and new technology to compare physical and chemical indicators and the rail surface straightness. Results shown that under high CE,by 0.5%~0.7%Cu＋0.2%~0.3%Cr＋0.035%~0.05%Sn complex alloying,low open box temperature（≤280 ℃）and stepped heating and cooling method thermal aging,a high rigidity and low stress bed HT300 casting could be produced. Compared with low CE high strength bed casting,high stiffness and low stress high CE bed casting had a relatively smaller amount of deformation,higher precision and accuracy performance.