JIS G3445 STKM19A Introduce

JIS G3445 is a standard carbon steel grade that is used in machinery and applications. It covers the dimensions, chemical composition, mechanical properties and requirements of the steel. The dimensions include the outer dimensions, wall thickness, inner dimensions, length and mass. The chemical composition includes the desired amount of carbon and the allowable levels of impurities such as sulfur and phosphorus. The mechanical properties include the strength, elongation, hardness and impact resistance of the steel.

Smelting temperature:1396°C - 1965°C

Application:Carbon steel pipe for mechanical structure

JIS G3445 STKM19A Material Chemical Composition

The chemical composition of the JIS G3445 STKM19A steel are as follows:

ElementMinMax
Silicon (Si)-0.5500
Sulfur (S)-0.0400
PhOsphorus (P)-0.0400
Manganese (Mn)-1.5000
Carbon (C)-0.2500

JIS G3445 STKM19A Material Mechanical Properties

The carbon content of the alloy makes it especially good for the production of heavy-duty and high-strength parts. JIS G3445 STKM19A steel exhibits a high level of ductility without any loss of strength. This, in combination with its good weldability, makes it ideal for applications that require forming and welding, as well as for machine shafts, gears, and axles.

The mechanical properties of the JIS G3445 STKM19A steel are as follows:

YieldRp0.2 ≤ 174 (MPa)
TeileRm≤ 247 (MPa)
ImpactKV/Ku42(J)
ElongationA43%
Reduction in cross section on fractureZ14%
As-Heat-Treated ConditionSolution and Aging, Annealing, Ausaging, Q+T,etc
Brinell hardness (HBW)311

JIS G3445 STKM19A Material Thermal Properties

The thermal performance parameters of the JIS G3445 STKM19A steel are as follows:

Temperature (°C)21728174
Modulus of elasticity (GPa)-397-
Mean coefficient of thermal expaion ×10-6/(°C)--44
Thermal conductivity (W/m·°C)-41.344.2
Specific thermal capacity (J/kg·°C)-312-
Specific electrical resistivity (Ω mm²/m)0.22--
Deity (kg/dm³)--142
Poisson’s coefficient, ν--241

JIS G3445 STKM19A Material Machining Technology

JIS G3445 STKM19A steel can be heat-treated at high temperatures to increase its strength and other mechanical properties. The alloy is very tolerant of heat up to 800°C. It is normally annealed at around 650°C and cooled slowly in order to recover its strength. On the other hand, when subjected to extreme temperatures, it is known to form martensite, an extremely hard form of steel that has a unique molecular structure. It is ideal for use in applications that require tremendous strength and wear resistance, such as high-pressure industrial applications.