# 입자강화 복합재료의 쐐기분열시험 및 파괴에너지 평가

• Accepted : 2016.01.27
• Published : 2016.03.01
• 40 74

#### Abstract

The effect of temperature on the fracture energy, crack propagation, and crack tip opening displacement (CTOD) was determined for particulate reinforced composites using the wedge splitting test. The materials that were used consisted of a polymer binder, an oxidizing agent, and aluminum particles. The test rate of the wedge splitting specimen was 50 mm/min, the temperature conditions were $50^{\circ}C$, room temperature, $-40^{\circ}C$, and $-60^{\circ}C$. The fracture energy, calculated from splitting load-crack mouth opening displacement(CMOD) curves, increased with decreasing temperature from $50^{\circ}C$ to $-40^{\circ}C$. In addition, the strength of the particulate reinforced composites increased sharply at $-60^{\circ}C$, and the composites evidenced brittle fracture due to the glass transition temperature. The strain fields near the crack tip were analyzed using digital image correlation.

#### Keywords

Wedge Splitting Test;Fracture Energy;Digital Image Correlation;Crack Tip Opening Distance (CTOD)

#### Acknowledgement

Grant : BK21플러스

Supported by : 충남대학교

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