摩擦点火Ti-V-Cr阻燃钛合金燃烧产物的组织特征  

Microstructure characteristics of burning products of Ti-V-Cr fireproof titanium alloy by frictional ignition

作　　者：弭光宝[1] 黄旭[1] 曹京霞[1] 王宝[1] 曹春晓[1] 

机构地区：[1]北京航空材料研究院,先进钛合金航空科技重点实验室,北京100095

出　　处：《物理学报》2016年第5期217-226,共10页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:51471155);航空科学基金(批准号:20123021004)资助的课题~~

摘　　要：采用摩擦氧浓度实验方法,结合原位观察、扫描电镜、能谱仪和X一射线衍射分析,系统研究Ti-V-Cr阻燃钛合金燃烧产物的微观组织形貌、燃烧反应过程的合金元素分布规律及微观机理.结果表明:Ti-V-Cr阻燃钛合金燃烧过程发出闪亮耀眼的白光,具有典型金属燃烧的火焰特征.燃烧产物主要有TiO_2,V_2O_5和Cr_2O_3三种氧化物,该混合氧化物以分散颗粒和致密连续体存在.分散颗粒为规则的球形;致密连续燃烧产物的微观组织具有分区特征,从合金基体至燃烧表面依次为过渡区、热影响区、熔凝区和燃烧区.其中,过渡区存在一些微小的颗粒状凸起,且有一定方向性;热影响区中形成大量V基固溶体相和少量的Ti基固溶体相,V基固溶体相上存在Ti的含量远高于基体的针状析出物;熔凝区中,大量的Ti基固溶体中存在少量的V基固溶体;燃烧区主要为Ti,V和Cr的氧化物混合物.热影响区的V基固溶体相降低了Ti元素向熔凝区的迁移速率,减慢了燃烧区Ti与O的优先反应;燃烧区形成的TiO_2,V_2O_5和Cr_2O_3混合氧化物和熔凝区O在Ti中大量固溶共同终止了O向合金基体的继续扩散,从而使Ti-V-Cr阻燃钛合金表现出优异的阻燃功能性.Titanium fire in the aero-engine is a typical accident caused by ignition and burning of titanium alloy,which leads to a huge damage.Some articles wrote it as ＂to turn pale at the mention of titanium＂.Fireproof titanium alloy,a new type of structural titanium alloy with fireproof function,has been developed to prevent titanium from fire hazard and to ensure safe and reliable service of aero-engine.In view of the lack of clear understanding of the microscopic mechanisms found currently for the structural functionality of fireproof titanium alloys,in this work,using frictional ignition technology in oxygen-rich environment（friction oxygen concentration method）,associated with in-situ observation,SEM,EDS and XRD analyses,the microstructure characteristics of burning products of Ti-V-Cr fireproof titanium alloys are investigated and the element distribution law associated with microscopic mechanism during combustion reaction process is disclosed.Results show that Ti-V-Cr fireproof titanium alloys produce dazzling white light during combustion,with the typical flame characteristics of metal combustion.The generated products after burning are mainly TiO2,V2O5 and Cr2O3oxides,in the form of dispersive particles and dense continuous body.The dispersive particles are in regular spheric shape,with a size of 10 50 μm;the dense continuous products after burning presents divisional feature.After the combustion lasts 18 s,four distinct zones form from the alloy matrix to the combustion surface and they are in the sequence of transitional zone,heat-affected zone fusion zone,and combustion zone,with sizes of 40 50,200 210,60 70,and 18 21 μm respectively.Further,some small granular shaped bulges exist in the transitional zone,in some fixed directions;in the heat-affected zone,a large number of V-based solid solution and some Ti-based solid solution form,and the titanium containing V-based solid solution is much higher than the needle-like precipitation phase in the matrix.In the fusion zone,there are some V-based solid

关 键 词：阻燃钛合金 燃烧产物 微观组织 钛火机理 

分 类 号：TG146.23[一般工业技术—材料科学与工程]