Crack Analysis of Servo Fuel Heater

A servo fuel heater of aircraft engine was found cracks when it was conducted quality inspection[1]. Through the macroscopic & microscopic observation, metallographic examination, chemical composition analysis, hardness test analysis, the characteristics of cracks, crack source generation and expansion process are studied[2]. It shows that the servo fuel heater crack was generated during the drawing process after extrusion, and occurred in the longitudinal direction due to the unreasonable drawing process[3]. No relationships with material were found in crack forming.