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金属成形过程很大程度上取决于刀具材料和润滑剂的选择。为了选择合适的组合，我们开发了一种测试摩擦系数、粘结和刀具磨损的新方法。本课题重点研究了刀具-工件界面的温度效应和尺寸效应对摩擦的影响，并对金属拉丝成形模具陶瓷材料的可行性进行了研究。对于温度效应和尺寸效应，从实验和理论上证实了刀具表面温升与界面尺寸有关。由此建立了一种预测摩擦系数的分析方法，该分析涉及润滑剂粘度的温度和压力敏感性、刀具和工件材料的热性能以及摩擦系数与进入刀具和工件表面间隙的润滑剂厚度之间的关系。该项目的目标大体上达到了。然而，各种实际金属成形过程的模拟尚未作为未来的工作进行；将需要关于实际过程的热条件的知识。此外，由于摩擦系数与润滑膜厚度之间的关系是一次近似关系，这一点还需要进一步详细研究。陶瓷材料的可行性研究也相当令人满意。结果表明，碳化硅的摩擦系数、抗磨性和抗粘性最好，氮化硅次之，氧化锆次之。在本项目中，采用拉丝法作为试验方法。在各种成形工艺中检验其可行性也很重要。

Metal forming processes are quite dependent on the choice of tool material and lubricant. For choosing appropriate combination of them, we have developed a new testing method for testing friction coefficient, sticking and tool wear. In this project, particular attention was paid to (1) temperature effect and (2) size effect of tool-workpiece interface on friction and also to feasibility study of ceramic materials for metal forming tools by wiredrawing.For the temperature effect and size effect, it was experimentally and theoretically confirmed that the temperature rise at the tool-surface is dependent on the size of the interface. An analytical method of predicting friction coefficient was thus developed; the analysis involves temperature and pressure sensitivity of the viscosity of the lubricant, thermal properties of the tool and workpiece materials and also a relationship between the friction coefficient and the thickness of the lubricant introduced into the gap between the tool and workpiece surfaces. The objectives of the project were by and large reached. However, the simulation of the various actual metal forming processes has yet to be undertaken as a future work; the knowledge on the thermal conditions for actual processes will be needed. Also, since the relationship between the friction coefficient and the lubricant film thickness was a first approximation, this should be investigated further in detail.The feasibility study of ceramic materials was also quite satisfactory. It was confirmed that silicon carbide is the best in view of friction coefficient, antiwear and antisticking; silicon nitride follows nest and zirconia the third. In this project, wire drawing was employed as a test method. It is also of importance to examine the feasibility in various forming processes.