ON THE SELECTION OF CRANKSHAFT STEEL FOR AERO-ENGINE AND ITS FUTURE REQUIREMENTS.

Abstract

Owing to the marked increase of aero-engine power, number of revolution, compression ratio, etc., crankshaft should inevitably biar the vibrational and duplicated over-stresses. The crankshaft should, therefore, not only be of the best chemical composition, most properly heat-treated, the latest metallurgical procedure being applied, but also of the most perfect design, in addition to the minimum weight and size.
The writer has published a part of this investigation in the "Tetsu To Hagane" Vol. XIX, No.4 In this paper, in order to select the most suitable steel for the future, the notch effect in regard to the endurance properties and the influence of heat-treatment of these steels have been investigated.
An investigation of crankshaft steel on the relation between the mechanical test results and the endurance properties by fatigue test have also been executed, and the writer has introduced a new method for determing the endurance limit in stead of laborious fatigue test.
As a conclusion, the writer has suggested future requirements for the aero-engine crankshaft steel, considering all the facts above mentioned.