Variation of Fatigue Properties in Nanoskinned Ti-6Al-4V - Rotating Bending and Axial Loading Tension-Compression Cycle -

Ti-6Al-4V 재의 UNSM 처리에 의한 피로특성변화 - 회전굽힘 피로시험과 축하중 인장압축 피로시험 비교 -

  • 서민수 (국민대학교 신소재공학부) ;
  • 편영식 (선문대학교 기계공학부) ;
  • 서창민 (경북대학교 기계공학부)
  • Received : 2011.12.15
  • Accepted : 2012.01.30
  • Published : 2012.04.01


Nanoskins were fabricated on a Ti-6Al-4V material by carrying out various surface treatments, i.e., deep rolling, laser shot peening, and ultrasonic nanocrystal surface modification (UNSM). These surface treatments are newly developed techniques and are becoming more popular for industrial applications. Fatigue tests were carried out using material test system (MTS); these tests included the axial loading tension-compression fatigue test (R = -1, RT, 5 Hz, sinusoidal wave) and rotating bending fatigue test (R = -1, RT, 3200 rpm). The analysis of the crack initiation pattern in the UNSM-treated material indicated that the crack was interior originating in the axial loading tension-compression cycle, and was surface originating in the bending fatigue test. UNSM treatment significantly improved the fatigue strength for the regime of above $10^6$ cycles that S-N curve of rotating bending stress clearly show the performance of a 5 mm titanium specimen after UNSM treatment is similar to that of an untreated 6 mm titanium specimen.


Ultrasonic Nanocrystal Surface Modification;Fish Eye Crack;Facet;Compressive Residual Stress


Supported by : 한국연구재단


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