http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Plasma Paste Boronizing법에 의한 Ni-Cr-Mo강의 붕화물층 생성거동과 내 토사마모특성에 관한 특성
조재현,박학균,손근수,윤재홍,김현수,김창규,Cho J. H,Park H. K,Son K. S,Yoon J. H,Kim H. S,Kim C. G 한국재료학회 2004 한국재료학회지 Vol.14 No.1
The surface property and formation behavior of a boride layer formed on Ni-Cr-Mo steel in a plasma paste boronizing treatment were investigated. The plasma paste boronizing treatment was carried out at 973~1273 K for 1-7 hrs under the gas ratio of Ar:H$_2$ (2:1). The thickness of the boride layer increased with increasing temperature and time in the boronizing treatment. The cross-section of the boride layer was a tooth structure and the hardness was Hv 2000~2500. XRD analysis revealed that the compound was identified as FeB, $Fe_2$B, and mixed phase of FeB/$Fe_2$B in the boride layer formed at 973~1073 K, 1173K, and 1273K, respectively. The Ni-Cr-Mo alloy boronized at 1173-1273 K showed the best excellent wear resistance against the sand. As a results of corrosion test in 1 M $H_2$$SO_4$ solution, $Fe_2$B formed on the matrix alloy exhibited higher corrosion resistance than FeB.
주변 소음이 휴대폰의 명료도에 미치는 영향에 관한 연구
장호경,박학균,김예현,강병용 嶺南大學校 基礎科學硏究所 1994 基礎科學硏究 Vol.14 No.-
To study the communication quality of mobile telephone, the articulation test was conducted in the anechoic- chamber in the condition of monaural and binaural which are controlled by frequency and sound pressure level. Also the articulation test was done in the traveling car speed with and without window closed. The experimental results showed that the articulation in the anechoic-chamber was decreased with noise level and the frequency was not affected, and the articulation in the traveling car was 50-60%. It was concluded with the experimental result that noise strongly affect mobile telecommunication quality in the big city.