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http://dx.doi.org/10.5228/KSTP.2012.21.1.67

Properties of a Helical Gear Due to the Manufacturing Process - Forged versus Machined Product  

Jung, H.C. (한국기계연구원 부설 재료연구소)
Kang, B.S. (부산대학교 항공우주공학과)
Lee, I.H. ((주)T.A.K)
Choi, S.T. ((주)T.A.K)
Sin, S.J. (현대자동차 변속기 생기팀)
Kang, S.H. (한국기계연구원 부설 재료연구소)
Lee, Y.S. (한국기계연구원 재료연구소 변형제어연구그룹)
Publication Information
Transactions of Materials Processing / v.21, no.1, 2012 , pp. 67-74 More about this Journal
Abstract
Although high productivity is possible, cold forged helical gears have not been widely used due to difficulty in achieving mechanical properties as well as dimensional accuracy of the product. Confidence in the gear characteristics also is very important in heavy-duty gear applications. Therefore, the properties of forged gears must be compared to the properties of conventional machined gears. The properties might be different due to the different fabrication processes. In this study, machined and forged products both before and after heat-treated have been compared by measuring the residual stress and involute curve of the tooth. Characteristics of hardness and microstructure were also compared. Additionally, tooth fracture strength was compared for the heat-treated products. Moreover, the tooth strength and the fracture pattern were compared between the machined and forged gears. The forged gear showed decreased changes in residual stress and decreased changes in dimensions when compared to the machined gear before and after heat treatment. The forged gear was over 10% better than the machined gear in tooth strength.
Keywords
Helical Gear; Forged Gear; Machined Gear; Residual Stress; Tooth Strength; Profile Curve;
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Times Cited By KSCI : 2  (Citation Analysis)
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