发动机研制中需对喉衬材料抗热震性能进行考核,发展了一种用小型固体发动机模拟全尺寸发动机热载荷对喉衬材料抗热震性能进行考核的缩比试验方法.通过保证推进剂、燃烧室压强、点火升压速率和喉衬型面等参数与全尺寸发动机接近,来保证热载荷的相似,同时适当兼顾喉衬应力的状态.采用该方法较好地再现了某型发动机出现的喉衬组件断裂飞出的故障,在一定程度上验证了方法的有效性.对2种C/C材料的抗热震性能进行了对比试验,试验结果表明,2种材料的抗热震性能明显优于故障发动机使用的三向绕纱C/C材料,其中炭布-穿刺C/C材料稍优于无纬布-穿刺C/C材料.%Thermal shock resistance of throat inserts material need be checked in rocket motor design. A subscale experimental method based on simulating the thermal load of full-size rocket motors throat insert with a subscale SRM is developed to examine the thermal shock resistance performance of throat inserts material. To obtain the thermal load approach, propellant, chamber pressure, rate of ignition pressurization and the contour of the surface of throat inserts should be guaranteed to be similar with those of full-size rocket motor, at the same time, stress condition of throat inserts is taken into account. This method has well repetitiveness of the fracture failure of throat inserts of a missile, which prove the feasibility of the test to a certain extent. A comparison test for thermal shock resistance of two different composite materials was carried out. The experimental results indicate that two C/C composite materials has good thermal shock resistance than three-directional woven C/C composite material used in the failure motor, and the performance of carbon fabric pierced C/C composite material is better than that of no woven fabric pierced C/C composite material.
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