PCD刀具加工强化复合地板中磨损行为的断裂力学研究

FRACTURE MECHANICS ANALYSIS ON WEAR CHARACTERISTICS OF POLYCRYSTALLINE DIAMOND TOOLS WHEN MACHINING HIGH PRESSURE LAMINATED FLOORING

本文首先利用断裂力学的理论,分析了聚晶金刚石刀具切削过程中的沿晶和解理两种磨损特征及其形成过程。通过采用SYNDITE聚晶金刚石刀具对Al_2O_3颗粒表层强化复合地板的切削加工实验,验证了理论分析的正确性。研究表明聚晶金刚石刀具铣削Al_2O_3表层强化复合地板的过程中,刀具的磨损特征主要由沿晶磨损和解理磨损组成。并且,理论和实验结果表明刀具的磨损特征受到金刚石晶粒尺寸的影响。粗粒度聚晶金刚石易产生解理磨损形貌,细粒度的聚晶金刚石易产生沿晶磨损形貌。同时,研究表明微观裂纹特征对聚晶金刚石刀具的磨损起着重要的作用。

In light of the fracture mechanics theory, the intergranular and cleavage wear characteristics of polycrystalline diamond (PCD) tool are analyzed firstly. Machining experiments of HPL (High Pressure Laminated) flooring are conducted by using SYNDITE PCD tools containing diamond of different grit size. From the theory analysis and experiments, it is shown that intergranular wear and cleavage wear are the main wear characteristics of PCD tools while machining HPL flooring. The wear character is affected greatly by diamond grain size of PCD. Cleavage wear tends to occur in PCD tools with coarse diamond grains, whereas intergranular wear in PCD tools with fine diamond grains. The research results show that micro cracks act as an important role in the wear process of PCD tools.