摘要
在基础固体渗硼剂(碳化硼和碳化硅)中分别添加氟硼酸钾、氧化铪、氧化锆和氧化镧(4%,质量分数)对TC4钛合金渗硼层的表面形貌、渗层厚度、硬度及渗层组织的影响进行了研究,并对其各自的作用机制进行了探讨,最终优选出最佳的催渗剂。结果表明:添加氟硼酸钾的渗层表面凹凸不平且腐蚀严重,与渗硼之前的试样相比,试样厚度明显减少,因此不能作为TC4钛合金固体渗硼的催渗剂;添加氧化铪的试样渗层表面形貌良好,但渗层疏松且薄,与基础渗硼剂的相比,厚度不仅未增加,反而有所减少(减幅为90.7%),因此也不能作为TC4钛合金的催渗剂;添加氧化锆、氧化镧的渗层表面形貌良好,与基础渗硼剂的相比,厚度与硬度得到显著提高(添加氧化锆增幅分别为30.1%和30.3%,添加氧化镧增幅分别为49.7%和90.2%),具有明显的催渗作用,因此能作为TC4钛合金固体渗硼的催渗剂;与添加氧化锆的渗层相比,添加氧化镧的渗层组织均匀致密,渗层更厚更硬(分别提高了15.1%和46.0%),具有更显著的催渗效果,是最佳的TC4钛合金固体渗硼的催渗剂。
The effects of adding KBF4, HfO2, ZrO2 and La203 （4%, mass fraction） respectively to basic solid boronizing agent （B4C and SiC） on the surface morphology, thickness, hardness, and the microstructure of the boronized layer on TCA alloy substrate were investigated, and the action mechanism was discussed, finally the best catalyst was selected. The results showed that the surface of the boronized layer by adding KBF4 was uneven and seriously corroded; and compared with the specimens before being boronized, the thickness of the botanized layer obviously decreased, so it could not be used as the catalyst of solid boronizing on TCA titanium al- loy. The surface of the botanized layer by adding HfO2 was good but the boronized layer was loose and thin; and compared with the basic boronizing agent, the thickness did not increase, but reduced（reduced by 90.7% ）, so it also could not be used as the catalyst of solid boronizing on TC4 titanium alloy. The surfaces of the boronized layer by adding ZrO2 and La203 respectively were good; and compared with the basic boronizing agent, the thickness and hardness of the boronizing layer were significantly improved （ZrO2 added was 30.1% and 30.3% , while La203 added was 49.7% and 90.2%, respectively）, so they could be used as the catalyst of solid boronizing on TCA titanium alloy. Compared with adding ZrO2, the microstructure of the boronizing layer by adding La203 was even and dense, and the thickness and hardness were higher （increased by 15.1% and 46.0%, respectively）. So La203 had a more significant catalytic effect and was the best catalyst of solid boronizing on TC4 titanium alloy.
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2014年第4期548-553,共6页
Chinese Journal of Rare Metals
基金
江苏大学拔尖人才工程基金项目(1211110001)
扬州市"八大产业"科技攻关与成果转化项目(YZ2011039)资助
关键词
固体渗硼
催渗剂
TC4钛合金
solid boronizing
catalysts
TC4 titanium alloy
