Ⅰ. INTRODUCTION
In fourth semester most of our department students attend the subject of mechanical manufacturing practice and we have made a bolt by ourselves. But the process was not a soft job. A bolt and nut is used diversely but it seemed that we don't know much about a importance and manufacture of bolts.
A bolt is a threaded fastener used in industry to make two or more mechanical
Test를 위해 Mechanical Bonding Test를 실시하여 Sn-Pb Solder와 Pb-Free Solder 간의 차이를 확인하고 Pb-Free Solder중에서도 각 재료마다의 Mechanical Bonding Test를 실시하여 Bonding Force를 체크한다. 보통 Soldering 된 제품이 받는 Stress 는 Tensile Stress 보다는 Shear Stress 가 주요하기 때문에 Solder 선택 시에는 Solder의 Tensile Property
무자극검사(NST, Non Stress Test)
NST는 태동-태아심박동증가 검사(Fetal activity-acceleleration test, FAT)라고도 부르며, 자극이 없는 상황에서 태아의 움직임과 심장 박동과의 관계를 보는 검사이다. 태아심음의 증가는 태아 움직임과 관련이 있다는 사실을 근거로 무자극 검사가 개발되었다. 검사를 통해 태아
같이 대 분류를 하였다.
A : Ferrous Metals(단 Casting의 Nonferrous Metals 中일부는 'A'로 분류됨)
B : Nonferrous Metals
C : Cementifious, Ceramic, Concreate and Masonry Materials
D : Miscellaneos Materials
E : Miscellaneous Subjects
F : Materials for Specific Applications
G : Corrosion, Deterioration, and Degradation of Materials
ES : Emergency Standards
P : Proposals
corrosion resistance that prevent corrosion of interior reinforcing rod because is alkalinity is security
3) have excellent modeling.
4) ability that have high hardness and stand in shock of pedestrian or machine operation etc. is big.
On the other hand, shortcoming is
1) withstand to Apchukryeok, force that press, but is weak in tensility, force that pull.
2) because weight is high than