摘要
针对牙科钴铬合金（remanium star CL）进行选择性激光熔融（SLM）成形实验,测试分析钴铬合金成形件微观组织及表面质量,研究激光功率、扫描速度、扫描间距及其综合作用下的激光能量密度对钴铬合金件表面粗糙度、相对密度及维氏硬度的影响。研究结果表明,相同激光能量密度下,不同的激光功率、扫描速度、扫描间距也会导致不同的表面粗糙度。SLM成形钴铬合金件相对密度随激光功率的增加而增大且变化速率逐渐缓慢;扫描速度在80~100 mm/s时,钴铬合金SLM成形相对密度最大值达94.95%。随着激光扫描间距的增大,钴铬合金件的相对密度下降。试件维氏硬度随激光功率和扫描速度的增大均呈现先增大后减小的变化规律。此外,激光功率从50 W变为100 W时,网状晶粒平均尺寸由0.8μm增大到2μm左右,然而过大的激光功率将导致晶粒尺寸过大使硬度降低。SLM成形钴铬合金件维氏硬度平均硬度为392 HV,在合理范围内略高于标准值。
Experiments are conducted to form dental cobalt chromium alloy part with selective laser melting method. By analyzing microstructure of the specimens, effects that processing parameters of laser power, scan speed, scan space and laser energy density exert on the surface roughness, relative density and hardness of cobalt chromium are studied. Research results show that different laser power, scan speed and spacing lead to different surface roughness although the laser energy density remains the same. Relative density of SLM cobalt-chromium alloy increases as the laser power increases and the rate of change slows down. When scanning speed varies from 80 mm/s to 100 mm/s, maximum value of SLM CoCr part reaches 94.95%. With the increase of laser scanning space, the relative density reduces. Besides, with laser power varying from 50 W to 100 W, net-shaped grain size increases from 0.8 ~m to 2 ~tm, while higher laser power will cause much bigger grain size and decrease the Vickers hardness. The average hardness of SLM CoCr part is 392 HV, slightly higher than the standard value within a reasonable range.
出处
《中国激光》
EI
CAS
CSCD
北大核心
2015年第5期63-70,共8页
Chinese Journal of Lasers
基金
国家自然科学基金(51375242)
一院高校联合创新重点基金项目(CALT201309)
浙江省重中之重学科开放基金
关键词
激光技术
选择性激光熔融
钴铬合金
表面粗糙度
相对密度
维氏硬度
laser technique
selective laser melting
cobalt-chromium alloy
surface roughness
relative densi- ty
Vickers hardness
