MIL-T-6736, 4130 Tube, Aircraft Quality

MIL-T-6736 Normalized, 4130 Tube, Aircraft Quality
STEELMAX Steel Story

MIL-T-6736 규정은 Alloy 4130 Chromium, Molybdenum 합금강재 규정으로
용접관 또는 Seamless 튜브 제품에 대한 Aircraft Quality 품질입니다.

MIL-T-6736 규정 제품은 Round, Rectangular or Square, Oval, Streamline
형상으로, 조건에 따라 Annealed, Normalized or Stress Relieving, QT 입니다.

MIL-T-6736 Tubing QT 열처리 하면 항복강도 100 ksi 이상의 높은 강도로
Chromium, Molybdenum 원소가 담금질성을 높여줍니다.

※ Stress Relieving (old name : stress relief annealing : 응력 제거 어닐링 (풀림)
Every piece of steel has an amount of internal stress caused
by steel production, machining, surface finish, heat treatment
and other processes.
During a heat treatment process the yield strength is reduced
to a lower level. If precision parts or complicated tools with
close tolerances, this deformation could cause problems.
In the case after rough machining and stress relieving is done
with a high degree of machining allowance.
After this process the internal stress is reduced by the parts deforming.
The standard process is slow heating up to 550~650℃, holding for
minimum 2 hours and finishing with a slow cooling in the furnace.

모든 철강재는 생산, 가공, 표면 마무리, 열처리와 기타 공정 진행에서
내부 응력이 어느 정도 쌓일 수 밖에 없고, 이런 내부 응력을 해소 시키려고
적당한 온도로 가열하고 균열화한 후, 적절한 온도로 냉각함으로써
실질적인 조직의 변화 없이 내부 응력을 줄이고자 시행하는 열처리를 말합니다.

※ Aircraft Quality Steel (AQ Steel : 항공기강 : 航空機鋼)
AQ Steel is the most commonly specified quality for general aerospace applications.
It is defined in SAE specification AMS 2301, which outlines the procedure for determining
compliance with cleanliness requirements by the magnetic particle inspection method.

MIL-T-6736, Alloy 4130
Chemical composition (%)	Carbon (C)	0.27~0.33
	Manganese (Mn)	0.40~0.60
	Phosphorus (P)	0.025 max
	Sulfur (S)	0.025 max
	Silicon (Si)	0.20~0.35
	Chromium (Cr)	0.80~1.10
	Molybdenum (Mo)	0.15~0.25

Alloy 4130 Normalized or Stress Relieved	Tensile Strength (psi)	Yield strength (psi)	Elongation (%)
t≤0.035″	95000	75000	10
0.035″＜t≤0.187″	95000	75000	12
t＞0.187″	95000	70000	15