複合組織鋼의 粒徑變化가 動的 破壞靭性에 미치는 影響 = Infouence of Grain Sizes on Dynamic Fracture Toughness of Dual Phase Steels

다국어 초록 (Multilingual Abstract)

In order to investigate grain size effect on dynanic fracture, raw material (SS41) was heat - treated with suitable process. Dynamic fracture toughness test was performed by an instrumented impact test ing machine with variations of the grain size, temperature ana impact loading velocity.
At room temperature, regardless of grain size the absorbed energy of dual phase steel is 0.25 MNm^(-1), which is about 10% of the raw material. But at -50℃, the absorbed energy of dual phase steel is shout the same as that of raw material. Therefore, raw material has higher absorbed energy than dual phase steel over all temperature region dynamic fracture toughness shows reverse behavior compared with the absorbed energy, that is, dual phase steel has dynamic fracture toughness value of 3500∼4500MPa√mm which is two times as large as that of raw material. For the case of variation in grain size of dual phase steel, the resulted dynamic fracture toughness is series A ≒ series B > series C at room temperature, In Kid - T behaviors, The curse of series A shows resemblance to that of series K, and series B to series C.
The smaller is the grain size of dual phase steel, the higher dynamic fracture toughness can be obtained.

목차 (Table of Contents)

• 目次 = 1
• Ⅰ. 序論 = 2
• Ⅱ. 試驗片 및 實驗方法 = 6
• 1. 試驗片 및 熱處理 = 6
• 2. 實驗裝置 및 方法 = 13
• 3. 動的破壞靭性의 評價 = 14
• Ⅲ. 實驗結果 및 考察 = 19
• 1. 母相粒徑에 따른 吸收에너지 = 18
• 2. 母相入徑에 따른 動的破壞靭性 = 22
• 3. 破面解析 = 24
• Ⅳ. 結論 = 29
• 參考文獻 = 30
• Summary = 34