EN24T, BS 817M40T, BS 970, Ni-Cr-Mo Alloy

EN24T, BS 817M40T, BS 970, Ni-Cr-Mo Alloy
STEELMAX Steel Story

BS 970 EN24T 는 Old Symbol, 현재는 BS 970 817M40T 재질은
Hardened and Tempered (QT) 열처리 된, 합금강재 재질입니다.

열처리 없는, Chemical only 인 경우는 EN24, 817M40 처럼
알파벳 “T” 가 빠진 Steel Symbol 입니다.

EN24T, 817M40T, 강한 인성을 가지는 합금강으로, 높은 강도, 인성,
내마모성이며 열처리성이 높은 원소의 합금으로, 열처리성이 높은 재질입니다.

EN24T, 817M40T 재질의 용도는 대형 축 (shafts). Gears (기어), spindles
bolts and studs, heavy-duty axles, machine structural, couplings 용도입니다.

※ Quenched and Tempered Steel (QT, 조질강 : 調質鋼)
Steel products quenched and tempered in other to obtain
the properties which high strength steels should have.

퀜칭 + 템퍼링 (담금질 + 뜨임) 열처리를 함으로서
고장력강으로서의 성질을 가지게 한 강재.

※ 열처리( Heat Treatment : 熱處理)
철강재의 전체 또는 일부에 열 사이클을 적용하여 그 성질 또는 조직을 변화 시키는
일련의 작업으로, 철강재의 화학 조성은 이러한 작업 과정으로 변할 수 있습니다.

Series of operations in the course of which a solid ferrous product is totally or
or partially exposed to thermal cycles to bring about a change in its
properties and/or structure.
The chemical composition of the ferrous product may possibly be
modified during these operations.

※ Toughness (인성 : 靭性)
Impact absorbing ability of steel without fracture. It is measured by
energy absorbed in an impact bending test. But the area below the
stress-strain curve in tensile testing is also a measure of toughness.
Steel, which is difficult to break has a high toughness.
Steel, which high toughness normally has a high ductility and is
difficult to break with impact energy.
Steels with low toughness are brittle.

EN24T, 817M40T
Chemical composition (%)	Carbon (C)	0.36~0.44
	Silicon (Si)	0.10~0.35
	Manganese (Mn)	0.45~0.70
	Phosphorus (P)	0.035 max
	Sulfur (S)	0.040 max
	Molybdenum (Mo)	0.20~0.35
	Chromium (Cr)	1.00~1.40
	Nickel (Ni)	1.30~1.70
Tensile Strength (MPa)		850~1000
Yield Strength (Mpa)		650 min
Elongation (%)		13 min
Hardness (HB)		240~302