Evaluation of Rolling Contact Fatigue Characteristics of Bearing and Rolling Materials by Mode II Fatigue Testing

Research Project

Project/Area Number	11650111
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Materials/Mechanics of materials
Research Institution	Nakanihon Automotive College
Principal Investigator	KO Haeng-nam Nakanihon Automotive College, Professor, 自動車工業科, 教授 (80141399)
Co-Investigator(Kenkyū-buntansha)	OTSUKA Akio Nagoya Univeristy, Professor Emeritus, 工学部・(愛知工大), 名誉教授(客員教授) (60022993) OGAWA Takeshi Aoyama Gakuin University, Professor, 理工学部, 教授 (50167318) KATOH Yasuo Nakanihon Automotive College, Lecture, 自動車工業科, 講師 (90259292) ITOGA Hisatake Nakanihon Automotive College, Assistant, 自動車工業科, 助手 (70310539) HASEGAWA Tatsuya Nakanihon Automotive College, Lecture, 自動車工業科, 講師 (30300156)
Project Period (FY)	1999 – 2001
Project Status	Completed (Fiscal Year 2001)
Budget Amount *help	¥3,200,000 (Direct Cost: ¥3,200,000) Fiscal Year 2001: ¥600,000 (Direct Cost: ¥600,000) Fiscal Year 2000: ¥700,000 (Direct Cost: ¥700,000) Fiscal Year 1999: ¥1,900,000 (Direct Cost: ¥1,900,000)
Keywords	Rolling contact fatigue / Flaking failure / Mode II fatigue / Testing method for fatigue crack / Aluminum alloy / High carbon chromium steel / ニッケルクロモリブデン鋼 / ニッケルクロムモリブデン鋼
Research Abstract	Flaking failure is the most common type of failure in rolling contact fatigue. This failure type is believed due to the subsurface crack growth under the contact surface. This subsurface crack growth is mode II fatigue crack growth under superimposed compression stress. Therefore, it is important to study the mode II fatigue behavior for evaluating rolling contact fatigue characteristics. The newly developed testing method is, as the former four-point-shear loading system, based on the principle that the static K_I and the compressive stress parallel to the pre-crack are superimposed to mode II loading, since it is difficult for the former apparatus to obtain the data under reversed loading. In the new apparatus, however, a direct loading system is employed instead of the four-point-shear loading system used in the former apparatus. The results obtained by the latter apparatus show that a mode II loading test for hard steel has become possible at arbitrary stress ratios, including fully reversed loading (R=- 1) which is the case of rolling contact fatigue.