摘要
目的提高纯钛表面的耐腐蚀性能。方法本实验主要分两步进行,首先进行金相样品的制备,然后利用强流脉冲电子束对材料表面进行改性处理,最后利用扫描电镜(SEM)、X射线衍射仪(XRD)、硬度检测,电化学检测等检测手段进行探讨研究。结果扫描电镜分析结果表明,强流脉冲电子束处理后,样品表面出现了熔坑,并且随着脉冲次数的增加,熔坑数量逐渐减少,这主要归因于强流脉冲电子束的净化除杂作用。X射线衍射分析发现,强流脉冲电子束处理后,衍射峰出现了宽化和向高角度偏移现象,主要归因于脉冲处理后合金表面的晶粒细化和表面应力、晶格常数的降低。另外,电化学测试表明,强流脉冲电子束处理后金属表面的耐腐蚀性明显增加,自腐蚀电流密度从强流脉冲电子束处理前的27.3μA/cm^2变化到25次脉冲处理后的6.3μA/cm^2,主要归因于强流脉冲电子束的净化除杂作用以及熔坑等结构缺陷的消失。显微硬度分析发现,经过强流脉冲电子束处理后由于样品表面的残余应力和孪晶等结构缺陷的存在,样品表面硬度明显降低。结论强流脉冲电子束处理后,纯钛的耐腐蚀性能增加,晶粒细化,硬度有所降低。
The work aims to improve corrosion resistance of pure titanium surface. This experiment was completed in two steps. A metallographic sample was firstly prepared, then the sample was modified by high current pulsed electron beam （HCPEB）, finally the treated sample was investigated using SEM, XRD, Vickers hardness tester and electrochemical test. The SEM analysis results showed that crater structures appeared on the surface and decreased as pulsed number increased, which was mainly attributed to purification effect of HCPEB. XRD analysis indicated that diffraction peaks were broadened after HCPEB treatment, which confirmed grain refinement on alloy surface after HCPEB treatment. Meanwhile, the peaks shifted to higher angles after HCPEB treatment, which was mainly attributed to decrease of lattice parameter and surface stress. In addi-tion, electrochemical test found that corrosion resistance of the alloy surface increased significantly after HCPEB treatment. Self-corrosion corrosion current density decreased from 27.3μA/cm2 to 6.3μA/cm2 by one order of magnitude after being treated by 25 pulses, which was attributed to the purification effect of HCPEB and elimination of crater structures. The micro-hardness test analysis showed the microhardness decreased significantly since residual stress and crystal twinning were present on sample surface after HCPEB treatment. The corrosion resistance of pure titanium is improved, grain is refined and hardness is decreased by high-current pulsed electron beam（HCPEB） treatment.
出处
《表面技术》
EI
CAS
CSCD
北大核心
2017年第7期156-160,共5页
Surface Technology
基金
国家自然科学基金(51671052)~~
关键词
纯钛
强流脉冲电子束
熔坑结构
耐腐蚀性
腐蚀电流
硬度
pure titanium
high current pulsed electron beam
crater structure
corrosion resistance
corrosion current
hardness
