DEVELOPMENT OF CLEAN LUBRICATION SYSTEM WITH GOOD LUBRICITY IN MANUFACTURING PROCESSES

目前的发展科学研究旨在开发一种在制造过程中使用超高相对分子质量聚环氧乙烯基润滑剂的清洁润滑系统，具有良好的润滑性，这是首席研究员等人所研究的。1.在正向挤压式和环压式摩擦试验中，证实了超高相对分子质量聚乙烯(UHMWPE)和硬脂酸钙的润滑性优于其他固体润滑剂，而水基UHMWPE润滑剂的润滑性与水基石墨润滑剂相同。2.开发了一种新的正反向挤出型摩擦试验方法，使在比环压试验等更恶劣的条件下能够对锻造过程中的润滑剂进行评价。该摩擦试验仪采用高频感应加热系统对工件进行加热，在机械压力机上安装了润滑剂喷雾系统和模具电阻加热系统。通过摩擦试验证实，在前向挤压锥模半角为10ﾟ、后向挤压面积减小为25、50、70%的条件下，可以合理地估算摩擦系数或摩擦剪切因数，且具有较好的重复性。结果表明，用UHMWPE润滑剂可以研制出润滑性好的清洁润滑体系。

The present developmental scientific research aimed to develope a clean lubrication system with good lubricity in manufacturing processes using ultrahigh molecular weight polyehylene based lubricant investigated by the head investigator et al.. The following conclusions were reached.1.It has been confirmed in forward extrusion type and ring compression type friction tests that a ultrahigh molecular weight polyethylene (UHMWPE) and a calcium stearate are superior in lubrictiy to other solid lubricants, and the water based UHMWPE lubricant has same lubricant has same lubricity as the water based graphite lubricant.2.A new friction testing method of forward-backward extrusion type was develped, enabling evaluation of lubricants for forging processes under more severe conditions than the upsetting such as ring compression test.The friction testing apparatus in which a high frequency induced heating system of workpiece, a spraying system of lubricants and an electric resistance heating system of die were installed into a mechanical press, was developed and manufactured.It has been confirmed by some friction tests that the values of friction coefficient or frction shear factor can be estimated reasonably with good reproducibility under the working conditions of 10ﾟ as the cone die half angle in forward extrusion and 25,50,70% as the reduction in area of backward extrusion.The UHMWPE lubricant and the graphite lubricant were tested in hot forgings of a stainless steel and aluminum alloys by the forward-backward extrusion type friction test, and those lubricants were evaluated in a workshop of hot forging of stainless steel. As a result, it has been confirmed that the clean lubrication system with good lubricity can be developed using the UHMWPE lubricant.