【摘要】 采用固体粉末法分别对基体组织为α-Ti的TA1和基体组织为(α+β)-Ti的TC4钛合金表面进行了渗硼,在偏光显微镜和扫描电镜(SEM)下观察了渗层的形貌,用X射线衍射(XRD)分析了渗层的物相组成.实验结果表明,渗硼温度在850~1000℃范围内,TA1表面渗层为平行于基体表面的多层结构,为Ti3O相和TiB相;当渗硼温度高于920℃时TiB为主要组成并出现了TiB2相,且硼钛化合物的含量随温度升高而增加.当渗硼温度低于1000℃时,TC4表面渗层为Ti3O相和TiB相,在渗硼温度高于1 000℃时,渗层为TiB2+TiB晶须结构.渗硼温度高于1 000℃是TA1和TC4表面形成硼钛化合物的充分条件.更多还原

【Abstract】 The solid powder boronizing,on the surface of titanium alloys with matrix structureα-Ti of TA1 and( α + β)-Ti of TC4,was investigated. The morphology of boride layer was observed by polarizing microscope and scanning electron microscope( SEM). The phase composition of boride layer was analyzed by X-ray diffraction( XRD). The results show that when boronizing temperature is in the range of 850 ~ 1 000 ℃,diffusion layers on TA1 in a multilayer structure are paralleled to the surface of the substrate,which composes of Ti3 O and TiB phases.When the temperature is higher than 920 ℃,TiB becomes the major component in the diffusion layer with TiB2,and the content of titanium borides increases with temperature. When the temperature is lower than 1 000 ℃,Ti3 O and TiB are the major components of the layer on TC4.When it is higher than 1 000 ℃,the layer is TiB2 and TiB whisker. Boronizing temperature above1 000 ℃ is the sufficient condition for the formation of titanium borides.更多还原