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Durability Assessment of Polyoxymethylen Using Ultrasonic Fatigue Testing

초음파 피로시험법을 이용한 엔지니어링 플라스틱 (Polyoxymethylen ; POM)의 내구성 평가

  • Received : 2014.03.12
  • Accepted : 2015.04.24
  • Published : 2015.08.01

Abstract

In this study, a newly developed ultrasonic fatigue test was performed for durability assessment of polyoxymethylene engineering plastic, which has a high crystallization rate and degree of crystallization. Fatigue strength of POM (polyoxymethylene) was performed on a piezoelectric UFT developed by Mbrosia Co., Ltd(1), operating at a high frequency of 20 kHz. The test results showed a fatigue limit of 5.0~6.0 MPa under fatigue testing at R = -1, 20kHz; and, electron microscopy revealed the size effect by risk volume and fractured dimple structure after the coalescence of micro-voids through the crazing effect, which occurs during the failure of a polymer.

Keywords

Ultrasonic Fatigue Test;Engineering Plastic;Polyoxymethylen;Dynamic Young's Modulus

References

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