YG8硬质合金表面沟槽织构的制备及其减摩特性

Preparation and Antifriction Characteristics of Groove Texture on YG8 Cemented Carbide Surface

采用光纤激光加工设备在YG8硬质合金表面加工出沟槽织构,研究了激光加工参数对织构尺寸及形貌的影响,得到最佳激光加工参数;采用最佳激光加工参数在硬质合金表面加工出4种不同方向的正弦型沟槽织构,研究了干摩擦条件下织构的减摩特性。结果表明:随着激光功率、扫描次数的增加或扫描速度的减小,沟槽织构尺寸增大,但过高的激光功率或过多的扫描次数导致织构底部粗糙;最佳激光加工参数为激光功率40W,扫描速度100mm·s-1,扫描次数200次,此时沟槽织构表面形貌较好,织构宽度为160μm,深度为15μm;在试验载荷为2N、滑动速度为20mm·s-1时,正弦中心线与摩擦方向成0°的正弦型沟槽织构的减摩效果优于正弦中心线与摩擦方向成30°,60°,90°的织构,且摩擦因数比光滑试样的降低了25%。

Groove textures were machined on the surface of YG8 cemented carbide by optical fiber laser processing equipment.The effect of laser processing parameters on the texture size and morphology was studied,and the optimum laser processing parameters were obtained.Four sinusoidal groove textures with different directions were machined on the surfaces of cemented carbide with the optimum laser processing parameters,and the antifriction characteristics of the texture under dry friction conditions were studied.The results show that with increasing laser power,increasing scanning time or decreasing scanming speed,the size of groove texture increased,but too high laser power or too many scanning times coarsened the texture bottom.The optimum laser processing parameters were laser power of 40 W,scanning speed of 100 mm·s-1 and scanning times of 200;with these parametens,the groove texture had relatively good surface morphology with width of 160μm and depth of 15μm.At the load of 2 Nand the sliding speed of 20 mm·s-1,the antifriction effect of the sinusoidal groove texture with sinusoidal center line at 0°to the friction direction was better than those with sinusoidal center lines at 30°,60°and90°to the friction direction,and the friction coefficient was 25%lower than that of the smooth sample.