舰载雷达天线稳定平台横摇滚珠丝杠断裂失效分析

Failure analysis of roll ball screw fracture in shipboard radar antenna stabilizing platform

针对某型舰载雷达天线稳定平台发生的横摇滚珠丝杠断裂问题,对失效滚珠丝杠开展失效分析。通过综合分析失效滚珠丝杠的断口分析、化学成分检测、金相检测、硬度检测与力学性能检测结果,认为滚珠丝杠螺纹退刀槽过渡圆角区表面残留的氮化白亮层导致表面脆性增加,促进了疲劳源的产生,材料调质处理后的抗拉强度、下屈服强度偏低,降低了材料的疲劳强度,在超过其疲劳承载极限的横摇交变载荷作用下发生疲劳断裂。通过对滚珠丝杠螺纹退刀槽部位采取防渗氮保护或渗氮处理后彻底去除氮化白亮层,同时优化调质处理工艺参数可以提高该滚珠丝杠的疲劳寿命。

In view of the roll ball screw fracture problem in a shipboard radar antenna stabilizing platform,a comprehensive failure analysis is conducted through fracture surface examination,chemical composition testing,metallographic inspection,hardness testing,and mechanical properties assessment,indicating that the presence of a nitrided white bright layer on the surface of the thread relief groove transition radius increases surface brittleness and generates fatigue sources.Additionally,the tensile strength and lower yield strength are found to be low after quenching and tempering treatment of the material,reducing its fatigue strength.Consequently,fatigue fracture occurs under alternating roll loads exceeding the fatigue bearing limit.To address this issue,protective measures such as avoiding nitriding treatment in the thread relief groove area or thoroughly removing the white bright layer after nitriding,along with optimizing the heat treatment process parameters,can be implemented.