(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)
摘 要: 采用摩擦点燃的方法，实验研究摩擦压力p和预混气流氧浓度xo对Alloy C+阻燃钛合金的抗点燃性能的影响，建立定量描述Alloy C+钛合金抗点燃性能的p—xo关系曲线，并结合SEM和XRD等手段分析Alloy C+钛合金的抗点燃机理。结果表明：Alloy C+钛合金的p-xo关系曲线符合抛物线规律，p在0.075~0.250 MPa变化时，着火对应的xo的变化范围约为20%；Alloy C+钛合金的抗点燃性能比TC4钛合金高40%以上；摩擦过程产生强烈的火花，着火首先发生在摩擦试样的中心孔内；摩擦表面由TiO2、V2O5和Cr2O3等氧化物融合物构成，厚度为2~5 μm，在摩擦过程中，该层融合物改善了接触表面的润滑条件，使摩擦区的温度大幅度降低，从而提高了阻燃钛合金的抗点燃性能。
关键字: 航空发动机；阻燃钛合金；阻燃性能；抗点燃性能；氧化物融合物；机理；钛火
（Aviation Key Laboratory of Science and Technology on Advanced Titanium Alloys,
Beijing Institute of Aeronautical Materials, Beijing 100095, China）
Abstract:The effect of friction contact pressure p and oxygen concentration xo of mixed airflow on the ignition resistance of Alloy C+ titanium alloy was studied by frictional ignition test, the relationship p—xo quantitatively describing the ignition resistance performance of Alloy C+ was established and the ignition resistance mechanism of Alloy C+ was analyzed by SEM and XRD, etc. The results show that the relationship p—xo of Alloy C+ obeys parabolic rule. The varying range of xo corresponding ignition is about 20% while p varies within 0.075-0.250 MPa. The ignition resistance performance of Alloy C+ is 40% higher than that of TC4. The violent sparks appears during friction process, and the origin of ignition is in the center hole of frictional sample. The surface under friction is composed of the fusion of the oxides including TiO2, V2O5, Cr2O3, etc, whose thickness is 2-5 μm, and this fused layer improves the lubrication condition between the contact surfaces, resulting in a dramatically decreases temperature in the friction area, and thus improves ignition resistance of fireproof titanium alloys.
Key words: aero-engine; fireproof titanium alloy; fireproof performance; ignition resistance performance; fused oxides; mechanism; titanium fire
