发动机振动诊断及振源分析法

This paper presents a progress in aircraft engine vibration monitoring and diagnosis in flight.Essentiality of the in-flight vibration monitoring and vibration source analysis and the features of the system used are discussed.An airborne vibration data acquisition unit,the ground analysis equipments and the method for analysing vibration signal are given.Its applications prove that it is feasible for vibration signal recording in flight and frequency spectrum analyzing.

不同线径镀锡铜包铝线最大电阻率的确定

为了给新制定的《镀锡铜包铝线》电子行业标准中具体线径范围内镀锡铜包铝线规定的最大直流电阻率提供理论支持,首先在镀锡铜包铝线规定的线径范围内选取最小的线径,再通过镀锡试验和金相分析测定镀锡层的最大厚度,然后根据铜包铝线的铜层体积比所规定的最大电阻率,采用理论计算的方法确定不同线径镀锡铜包铝线的最大电阻率。