http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
CW Nd:YAG 레이저를 이용한 구조용 합금강 SCM4의 표면경화 특성
신병헌(Byung Heon Shin),유영태(Young Tae Yoo),신호준(Ho Jun Shin) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.11
Laser surface hardening is a beneficially used for surface treatment of structual steel. Due to very rapid heating and cooling rates, structual steel(SCM4) can be hardened as self quenching. The aim of this research project is to improve the influence of the process laser parameters: laser power, spot size, surface roughness, and traverse speed. The laser beam is allowed to scan on the surface of the work piece at constant the power(1095W), varying the traverse speed between 0.3 to 0.8m/min.. The optical lens with the elliptical profile is designed to obtain a wide surface hardening area with a uniform hardness. From the results of the experiment, it has been shown that the stable hardness is about 600Hv~700Hv, when the laser power, focal position and the traverse speed are 1095W, 0㎜, 0.3m/min.
신병헌(Byung-Heon Shin),유영태(Yung-Tae Yoo),신호준(Ho-Jun Shin),윤철중(Chul-Jung Yun) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.6
Laser welding of metals has been widely used to improve a wear resistance and a corrosion resistance of the industrial parts. The objective of this research works is to investigate the influence of the process parameters, such as the welding for metals with CW Nd:YAG lasers. The bead-on-plate welding tests are carried out for several combinations of the experimental conditions. In order to quantitatively examine the characteristics of the butt welding, the welding quality of the cut section, stain-stress behavior and the hardness of the welded part are investigated. From the results of the investigation, it has been shown that the optimal welding condition without defects in the vicinity of the welded area and with a good welding quality is 1325W of the laser power, and 1.4m/min of laser welding speed.
SM45C 중탄소강의 CW Nd:YAG 레이저표면경화와 고주파표면경화특성 비교
신호준(Ho-Jun Shin),유영태(Young-Tae Yoo),안동규(Dong-Gu Ahn),신병헌(Byung-Heon Shin) 대한기계학회 2005 대한기계학회 춘추학술대회 Vol.2005 No.11
Laser heat treatment technology is used for improving the feature of fatigue resistance and wear resistance in mobile parts. The purpose of this study is to compare the characteristics of laser heat treatment and high frequency heat treatment, which is commonly used in industrial place. For the preemptive experiment, the distribution, depth and size of hardening and its micro-structural features were compared between surface heat treatment case by defocusing and variables of each process for heat treatment by exclusively manufactured heat treatment optical system. As a result, high frequency heat treatment has wide distribution of hardening depth and width about 3 times larger than laser heat treatment, however, its average hardness showed 621.4Hv which is smaller than the average hardness of laser heat treatment with 691Hv.
니켈도금된 중탄소강의 Nd:YAG 레이저 용접에서 맞대기 및 겹치기 용접 특성
신호준(Ho-Jun Shin),유영태(Young-Tae Yoo),신병헌(Byung-Heon Shin),안동규(Dong-Gyu Ahn) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.11
In spite of its good mechanical characteristics, S45C carbon steel has a high carbon contents and suffers a limitation in the industrial application due to the poor welding properties. Laser welding of metals has been widely used to improve a wear resistance and a corrosion resistance of the industrial parts. The objective of this research works is to investigate the influence of the process parameters, such as the welding for metals with CW Nd:YAG lasers. The bead-on-plate welding tests are carried out for several combinations of the experimental conditions. In order to quantitatively examine the characteristics of the welding quality of the cross section, stain-stress behavior and the hardness of the welded part are investigated in comparison of the Ni coated steels and Ni uncoated steel.
CW Nd:YAG레이저를 이용한 금형강 SKD61의 표면열처리
신호준(Ho-Jun Shin),유영태(Young-Tae Yoo),안동규(Dong-Gyu Ahn),신병헌(Byung-Heon Shin) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.6
Laser surface hardening technologies have been used to improve characteristics of wear and to enhance the fatigue resistance for mold parts. The objective of this research work is to investigate the influence of the process parameters, such as power of laser and defocused spot position, on the characteristics of laser surface hardening for the case of SKD61 steel. CW Nd:YAG laser is selected as the heat source. The optical lens with the elliptical profile is designed to obtain a wide surface hardening area with a uniform hardness. From the results of the experiments, it has been shown that the maximum hardness is approximatly 740 Hv when the power, focal position and the travel of laser are 1,095 W, +1㎜ and 0.3 m/min, respectively. In addition, the hardening width using the elliptical lens was three time larger than that using the defocusing of laser beam.