旋转超声磨削加工中刀具结合剂类型与加工性能的关系

Relationship between bond patterns of tools and working performance in rotary ultrasonic grinding

实验分析了硬脆材料旋转超声磨削过程中刀具结合剂类型对加工性能的影响以便提高加工精度和加工表面的完整性。首先,采用能谱分析研究了铁基、陶瓷基和青铜基3种超声振动刀具中结合剂与金刚石颗粒的把持形式,并根据相同加工工艺条件下刀具磨损形式确定了把持力大小。然后,结合超声振动刀具特性,通过旋转超声磨削加工实验研究刀具结合剂类型与切削力、刀具磨损量、加工表面完整性的关系,并对实验结果进行了分析。实验结果表明:相对于陶瓷基和青铜基结合剂超声振动刀具,铁基结合剂超声振动刀具把持力最大,Z轴切削力平均值最小(为46.8N);加工18 000mm3材料后,刀具轴向磨损量最小(为0.1mm);而陶瓷基结合剂超声振动刀具加工表面质量最好,表面粗糙度最大值为21.79μm。结果证实铁基超声振动刀具适用于粗加工,陶瓷基超声振动刀具则适用于精加工。

For improving the machining precision and surface integrity of hard and brittle materials in rotary ultrasonic grinding, the influence of bond patterns of tools on working performance was ana- lyzed. First, the bonding patterns between diamond particles and bonds in ceramics-bonded, iron- bonded and bronze-bonded tools were investigated by energy spectral analysis, and bonding strength was confirmed according to the tool wear of the same process parameters. Based on results above and the characteristics of ultrasonic vibration tool, the relationship between bond patterns and cutting force, tool wear, surfaces integrity was studied by rotary ultrasonic grinding machining experiments. Experimental results indicate that average cutting force in Z axis is 46.8 N and the tool wear of after removing 18 000 mma is 0.1 mm by iron-bonded ultrasonic vibration tool, they are smaller than those of ceramics-bonded and bronze-bonded tools. However, the ceramics-bonded ultrasonic vibration tool is the best one, and its surface roughness is 21.79 μm. These results prove that the iron-bonded ultra- sonic vibration tool is suitable for rough maching and the ceramics-bonded ultrasonic vibration tool is favourable to finish maching.