Previous issue | > Previous issue |
|
|
|
|
507 |
Microstructures and Oxidation Behaviors of Silicide Coated Nb Alloys by Halide Activated Pack Cementation Process
Halide activated pack cementation에 의한 silicide 코팅층의 형성에 따른 Nb 합금의 산화거동
Wonchul Yang, Choong-Heui Chung, Sangyeob Lee, Kyeong Ho Baek, Youngmoo Kim, Seong Lee, Joon Sik Park양원철, 정중희, 이상엽, 백경호, 김영무, 이성, 박준식
Korean J. Met. Mater. 2020;58(8):507-514. Published online 2020 Aug 5 DOI: https://doi.org/10.3365/KJMM.2020.58.8.507
Abstract
In this study, we tried to improve the oxidation resistance of Nb-12Si (wt%) alloys at 1200 °C or higher through pack cementation coatings. Nb-12Si (wt%) alloys were prepared by arc-melting under Ar atmosphere. When the alloys were coated using pack powder mixtures composed of Si, Al 2O 3 and NaF, two silicide..... More
|
|
|
515 |
A Further Study on Knoop Indentation Plastic Deformation for Evaluating Residual Stress
Woojoo Kim, Kyungyul Lee, Jong-hyoung Kim, Young-Cheon Kim, Dongil Kwon
Korean J. Met. Mater. 2020;58(8):515-521. Published online 2020 Jul 27 DOI: https://doi.org/10.3365/KJMM.2020.58.8.515
Abstract
A method for evaluating residual stress using an instrumented indentation test was developed some decades ago. More recently, another method was developed, using a Knoop indenter. The conversion factor ratio, which is one of the key factors in the evaluation algorithm, has been taken to be 0.34, although this value..... More
|
|
|
522 |
Evaluation of Transition Temperature in Reactor Pressure Vessel Steels 6using the Fracture Energy Transition Curve from a Small Punch Test
소형펀치 파단에너지 천이곡선을 활용한 원자로용기강의 천이온도 평가
Tae-kyung Lee, Seokmin Hong, Jongmin Kim, Min-Chul Kim, Jae-il Jang이태경, 홍석민, 김종민, 김민철, 장재일
Korean J. Met. Mater. 2020;58(8):522-532. Published online 2020 Jul 27 DOI: https://doi.org/10.3365/KJMM.2020.58.8.522
Abstract
The small punch (SP) test is one of the small specimen test techniques, and standardization of the SP test method for evaluating the mechanical properties of metallic materials is in progress. In this study, the impact transition temperature of reactor pressure vessel steels (RPV) in nuclear power plants was estimated..... More
|
|
|
533 |
Property Evaluation of Tungsten-Carbide Hard Materials as a Function of Fe Contents
Fe 함량변화에 따른 텅스텐카바이드 초경소재의 특성평가
Ju-Hun Kim, Jeong-Han Lee, Junho Jang, Ik-Hyun Oh, Sung-Kil Hong, Hyun Kuk Park김주훈, 이정한, 장준호, 오익현, 홍성길, 박현국
Korean J. Met. Mater. 2020;58(8):533-539. Published online 2020 Jul 27 DOI: https://doi.org/10.3365/KJMM.2020.58.8.533
Abstract
In this study, consolidated WC-Fe compacts as a function of Fe contents were fabricated by a spark plasma sintering method, following the mixed by the ball-milled powder. Fe among the metallic binders was added to WC enhance not only the driving force of sintering process but also suppressing the grain..... More
|
|
|
540 |
Effect of Aging Heat Treatment Conditions on the Mechanical Properties and Microstructure of Base and Weld Metal of Alloy 282 Superalloy
Alloy 282 초내열합금 모재 및 용접부의 기계적 특성과 미세조직에 미치는 시효열처리 조건의 영향
Jinhyeok Bang, Yongjoon Kang, Namkyu Kim, Seong-Moon Seo, Sanghoon Lee, Sangwoo Song, Namhyun Kang방진혁, 강용준, 김남규, 서성문, 이상훈, 송상우, 강남현
Korean J. Met. Mater. 2020;58(8):540-549. Published online 2020 Jul 27 DOI: https://doi.org/10.3365/KJMM.2020.58.8.540
Abstract
The effect of aging heat treatment conditions on the mechanical properties and microstructure of the base and weld metal of Alloy 282 superalloy was investigated. The aging heat treatment conditions employed in this study were as follows: two-steps (1010 °C for 2 hours plus 788 °C for 8 hours) and..... More
|
|
|
550 |
A Study on the Supersonic Jet Nozzle to Improve of the Operating Efficiency of the Converter Process
전로 공정 조업 효율 향상을 위한 초음속 제트 노즐 연구
Jae-Hong Kwon, Ji-A Lee, Kyeng-Uk Lee, Jeong-Whan Han권재홍, 이지아, 이경욱, 한정환
Korean J. Met. Mater. 2020;58(8):550-559. Published online 2020 Jul 27 DOI: https://doi.org/10.3365/KJMM.2020.58.8.550
Abstract
Recently, various worldwide studies have been conducted to improve converter operation by modifying the lance nozzle. In this study, a numerical analysis of the lance nozzle was conducted to improve the dephosphorization efficiency, and to reduce blowing time. The lance nozzle was designed in the form of an abnormal expansion..... More
|
|
|
560 |
Improvement of Wear Resistance in Laser Shock-Peened Copper Contacts
Donghyuck Jung, Changkyoo Park, Eun-Joon Chun, Yoon-Jun Kim
Korean J. Met. Mater. 2020;58(8):560-565. Published online 2020 Jul 27 DOI: https://doi.org/10.3365/KJMM.2020.58.8.560
Abstract
This study investigated the influence of laser shock peening without coating (LSPw/oC) on the degradation of copper electrical contacts. A theoretical calculation of the plastic-affected depth (PAD) induced by LSPw/oC was performed, based on the laser-induced plasma pressure along with the Hugoniot elastic limit of our LSPw/oC experimental conditions. The..... More
|
|
|
566 |
Extended Energy Conservation Law in Alloys: the Absence of Energy Non-Equilibrium
Myung Sik Choi, Han Gil Na, Changhyun Jin, Kyu Hyoung Lee
Korean J. Met. Mater. 2020;58(8):566-572. Published online 2020 Jul 27 DOI: https://doi.org/10.3365/KJMM.2020.58.8.566
Abstract
Assuming that many of the materials produced in a non-equilibrium state remain unchanged, an extended space–energy conservation law was proposed based on the existing energy conservation law. In the present study, by analyzing the well developed equilibrium binary phase diagram of iron (Fe) – carbon (C), we show that energy..... More
|
|
|
573 |
Effects of Al-Si Coating Thickness on 22MnB5 in Hot Stamping Wear
Al-Si 도금층 두께가 22MnB5강의 핫스탬핑 공정 마모에 미치는 영향
Min Ki Ji, Hyunsung Son, Jinkeun Oh, Seongwoo Kim, Kyungmok Kim, Tea-Sung Jun지민기, 손현성, 오진근, 김성우, 김경목, 전태성
Korean J. Met. Mater. 2020;58(8):573-582. Published online 2020 Jul 27 DOI: https://doi.org/10.3365/KJMM.2020.58.8.573
Abstract
Al-Si coated ultra-high strength steels (UHSS) are widely used in automotive applications because of their high strength-to-weight ratio, corrosion protection and good weldability. The hot stamping (also called hot press forming) process is an effective and suitable technique for producing automotive parts from Al-Si coated UHSS. However, critical issues, such..... More
|
|
|
|
|