http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
스테인리스강의 가스질화에 미치는 열처리 조건의 영향에 관한 연구
김한군 ( H. G. Kim ),황길수 ( G. S. Hwang ),선철곤 ( C. G. Sun ) 한국열처리공학회 2003 熱處理工學會誌 Vol.16 No.2
N/A Nitrided compound layer and diffusion layer structure were observed by SEM. The compound layer and the constituent of nitrided surface of STS 304, STS 316, STS 410 and SACM 645 steel were analysed using EMPA and XRD respectively. The depth of nitriding layer that is obtained from similar nitriding condition decrease in the order of SACM 645>STS 410>STS 316>STS 304. Result of phase transformation of the nitrided at 550℃ by XRD analysis were as follows; The austenitic stainless steel was mainly consist of Cr_2N accompanying with Fe_4N and Fe_2-3N phase and martensitic stainless steel was mainly consist of present Fe_2-3N+Cr_2N phase, but SACM 645 steel was Fe_2-3N phase present only.
GCD 45 중심부 조직 및 기계적 성질에 미치는 ADI 열처리 조건의 영향
김한군(H . G . Kim),유용주(Y . Z . You),이재식(J . S . Lee),정태영(T . Y . Chung) 한국열처리공학회 2002 熱處理工學會誌 Vol.15 No.1
N/A The effect of ADI heat treatment conditions on the core microstructures and mechanical properties of GCD 45 has been investigated. In the case of 25βÆ in diameter, it has been found that pearlite structure is not obtained, and the matrix is consisted of graphite, bainite and retained austenite. Upon cooling isothermally from 900℃, the core structure of 35 mm in diameter is converted to pearlite. However, the structure is transformed to bainite after slow cooling from 900℃ to 800℃.
김한군 ( H. G. Kim ),김윤현 ( Y. H. Kim ) 한국열처리공학회 2004 熱處理工學會誌 Vol.17 No.5
N/A Effect of pre-treatment on the gas nitriding process of austenitic stainless steels has been investigated and the following results were obtained. Minimum pre-treatment time was decreased to 5min with increasing treatment temperature from 200℃ to 600℃. Surface activation effect by the pre-treatment was maintained in the air to holding time of 64hr, judging from the analysis result of gas nitrided specimens. The Depth of nitrided layer of STS 304 and 316 stainless steels were ranged from 5μm to 90μm at 440℃-600℃. The X-ray diffraction intensity for austenitic stainless steels were increased as nitriding temperature from 440℃ to 600℃.
스테인리스강의 내식성에 미치는 저온 플라즈마 질화의 영향
김한군 ( H. G. Kim ),빈정욱 ( J. U. Bin ) 한국열처리공학회 2011 熱處理工學會誌 Vol.24 No.1
Plasma nitriding of stainless steels has been investigated over a range of temperature from 400 to 500℃ and time from 10 to 20 hours. Characterization of systematic materials was carried out in terms of mechanical properties and corrosion behaviors. The results showed that plasma nitriding conducted at low temperatures not only increased the surface hardness, but also improved the corrosion resistance of STS 316L, STS409L, and STS 420J2. It was found that plasma-nitriding treatment at 500℃ resulted in increasing the corrosion performance of STS 409L and STS 420J2, while STS 316L was observed with server and massive damage on surface due to the formation of CrN. (Received November 27, 2010; Accepted December 19, 2010)
전자비임 용접된 300Grade 18% Ni 마르에이징강 박판의 이음강도에 미치는 열처리의 방향
정병호,김한군,강순배,김우열,박흥일 ( B . H . Jung,H . G . Kim,S . B . Kang,W . Y . Kim,H . I . Park ) 한국열처리공학회 1993 熱處理工學會誌 Vol.6 No.4
The effect and Condition of heat treatment on the tensile strength of welded joint was investigated in 300 grade 18% Ni-Co-Mo-Ti maraging steel sheets welded with electron beam. A good tensile strength of welded joint was obtained by following heat treatment cycle ; At 1100℃ the specimen was high temperature solution treated for 1 hour and then it was repeated solution treated at 900℃, 820℃ for 1hour respectively to recrystallize the coarsened γ grain. These heat treatment cycle was completed by an final aging heat treatment at 480℃ for 4 hour. Moreover, dissolution of dendrite, a significant decrease in seregation of Mo, Ti in weld metal were observed and also the coarsened γ grain formed at 1100℃, 1200℃ changed to fine grain due to the effect of recrystallization.
김용현,김영훈,김한군 ( Y . H . Kim,Y . H . Kim,H . G . Kim ) 한국열처리공학회 1997 熱處理工學會誌 Vol.10 No.1
The variation of the mechanical properties and the formation of retained austenite with heat treatment conditions in austempered Si bearing carbon steels has been investigated. In the case of a steel containing 0.35C-1.48Si-0.95Mn, it has been found that a feather shape bainite structure of lath are obtained under a isothermal treated condition at just below the Ms temperature, and the martensite, bainitic ferrite and retained austenite of second phase particles on the ferrite matrix for a isothermal treated steels after intercritical annealing are precipitated in a linked shape. The retained austenite with 2㎛ size induced as TRIP is found to increase with increasing the formation rate of retained austenite for the intercritical annealing and high Si containing steels. The tensile strength is increased as austempering temperature increases in all isothermal treatment temperature, whereas the elongation is shown to roughly decrease as the tensile strength increases. The values of tensile strength-elongation balance have showed a marked dependence upon the elongation rather than the tensile stregth, and their values are increased for high Si containing steels and intercritical annealing condition. The most optimum result has been shown to be the tensile stregth-elongation balance of 2882.4kgf/㎟.% and the elongation of 33.3% for a B steel in the heat treating temperature range of 780∼370℃.