基于选择性激光烧结(SLS)技术, 在不同工艺参数组合下,分析了激光扫描速度、激光功率、分层厚度、扫描间距以及预热温度等工艺参数对SLS原型件强度与尺寸精度的影响。研究结果表明, 各烧结工艺参数均会影响原型件的烧结强度和尺寸精度, 且各因子之间存在交互作用。当激光功率为40 W、扫描速度为2500 mm·s-1、扫描间距为0.15 mm、分层厚度为0.20 mm、预热温度为60 ℃时, 烧结强度与尺寸精度达到最优。在此基础上, 结合传统砂型铸造方式, 实现了全新高端工程机械液压多路阀的快速铸造, 验证了基于SLS技术的快速铸造液压元件的可行性。

Based on the selective laser sintering (SLS) technique, the influences of the process parameters including scanning speed, laser power, layer thickness, scanning spacing, and preheating temperature on the strength and dimensional precision of SLS prototype parts are analyzed under different process parameter combinations. The study results show that, all the sintering process parameters can affect the sintering strength and dimensional precision of prototype parts, and there exist interactions between various factors. When the laser power is 40 W, the scanning speed is 2500 mm·s-1, the scanning spacing is 0.15 mm, the layer thickness is 0.20 mm, and the preheating temperature is 60 ℃, the optimal sintering strength and dimensional precision can be obtained. Based on these results, by combining the traditional sand casting method, a new advanced-construction-machinery hydraulic valve is rapidly casted, which verifies the feasibility of rapid casting process of hydraulic components based on the SLS process.