Study on Fatigue Property of Material for Oil Hydraulic Piston Pump

유압 피스톤 펌프 소재의 피로특성 연구

  • Kim, Nam-Seok (Dept. of UR Interdisciplinary Program of Mechanical Engineering Graduate School, Pukyong Nat'l Univ.) ;
  • Nam, Ki-Woo (Div. of Advanced Materials Science and Engineering, Pukyong Seoul Nat'l Univ.) ;
  • Kim, Hyun-Soo (R&D Center, Sam-ho Precision)
  • 김남석 (부경대학교 대학원 기계공학과) ;
  • 남기우 (부경대학교 신소재공학부) ;
  • 김현수 (삼호정밀 기술연구소)
  • Received : 2010.12.10
  • Accepted : 2011.02.24
  • Published : 2011.05.01


Oil hydraulic piston pumps are extensively used worldwide because of their simple design, light weight, and cost effectiveness. However, an oil hydraulic pump is likely to have high leakage, friction, and low energy efficiency after long-term use. In oil hydraulic piston pumps the clearance between the valve block and the piston plays an important role in the volumetric and overall efficiency. We studied the wear property of the SACM645 material used in hydraulic piston pumps via experiments with different heat treatments. We prepared three different specimens. The maximum tensile strengths of the QT and QT-nitration specimens are similar (about 820 MPa), but the strains are significantly different. However, the fatigue characteristic depended on the heat treatment.


Fatigue Property;Fatigue Limit;SACM645 Material;Heat Treatment;Oil Hydraulic Piston Pump


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