# 고체추진제의 파괴인성에 대한 온도 및 두께의 영향

• Seo, Bo Hwi (Dept. of Mechanical Design Engineering, Chungnam Nat'l Univ.) ;
• Kim, Jae Hoon (Dept. of Mechanical Design Engineering, Chungnam Nat'l Univ.)
• 서보휘 (충남대학교 기계설계공학과) ;
• 김재훈 (충남대학교 기계설계공학과)
• Accepted : 2013.06.18
• Published : 2013.11.01
• 64 14

#### Abstract

A cracked solid propellant would have failure or fracture of rocket because of excessive combustion according to increase of burning area, therefore it is important to evaluate the fracture toughness of solid propellant. A procedure is used to investigate the material under a range of test temperatures between -60 and $60^{\circ}C$, three kind of specimen thickness, 4, 12.5 and 24.5 mm to determine the effect of two parameters on the fracture toughness. A center cracked tension (CCT) specimen is used in these tests, which were conducted using INSTRON 5567 testing machine and environmental chamber to evaluate the fracture toughness. The experimental results show that the fracture toughness tends to decreases with an increase in the temperature, and the effect of thickness indicates that the fracture toughness is highest at 12.5 mm under various temperatures except $-60^{\circ}C$. It is found that the fracture toughness of solid propellant is changed due to glass transition behavior around $-60^{\circ}C$.

#### Keywords

Solid Propellant;Fracture Toughness;Viscoelasticity;Stress Relaxation

#### Acknowledgement

Supported by : 국방과학연구소

#### References

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#### Cited by

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2. Wedge Splitting Test and Fracture Energy on Particulate Reinforced Composites vol.40, pp.3, 2016, https://doi.org/10.3795/KSME-A.2016.40.3.253
3. Structural Integrity of Aged Hydroxyl-Terminated Polybutadiene Solid Rocket Propellant vol.34, pp.1, 2018, https://doi.org/10.2514/1.B36496