高張力鋼 및 硬鋼의 硫化物腐蝕破壞에 關한 硏究 = Some Studies on the Sulfide Corrosion Cracking of 55 kg/mm Class high strength Steels and Hard Steels

다국어 초록 (Multilingual Abstract)

We discussed the embrittlement of 55 kg/㎟ class high strength steels which occured when they were immersed in a 0.5% acetic acid solution sataturated with H₂S at the room temperature, and about the effect of immersion in this solution on the time to failure of sulfide corrosion cracking. Further we discussed the diffusivity of hydrogen in steel.
The conclusions are as follow;
(1) The effect of pre-strain on sulfide corrosion susceptibity depends on the structure of steel. It is regarded as behaviour of dislocations vacancies and penetrating partides.
(2) In the material of which the structure was tempered martensite, the time to failure lengthened with the increase of pre-strain beyond the uniform elongated zone. In the material like H.T.55, the time to failure shortened with the increase of pre-strain all over the zone of pre-strain. In the material of which the structure was ferrite plus pearlite. The time to failure lengthened with the increase of pre-strain until the test piece began local shrinkage, but beyond this region of pre-strain the time to failure did not materially change.
This is regarded as action of non-metallic impurities, defects occured entering from uniform elongaated zone to local shrinkage.
(3) The mechanism of diffusion of hydrogen into materials is independent of structure change by heat-treatment.

목차 (Table of Contents)

• Abstract
• 1. 緖論
• 2. 實驗方法
• 3. 實驗結果
• 4. 考察
• 5. 結論
• 參考文獻