SAE J404 87L20 Introduce
The SAE J404 steel standard is an industry-wide specification for a variety of steel grades. It was developed in response to changes in the automotive industry, and is designed to ensure the proper selection and use of steel for automotive applications. The standard is divided into four main subsections, which cover the chemical composition, physical properties, forming, and heat treating of steels.
Smelting temperature:1221°C - 1695°C
Application:Chemical compositions of SAE alloy steels
SAE J404 87L20 Material Mechanical Properties
The alloying elements present in SAE J404 87L20 steel endow it with a range of mechanical properties. It is a relatively low-carbon steel, meaning that it is fairly soft and ductile and can be easily machined and welded. This makes it a popular choice for a wide range of applications. The steel has an ultimate tensile strength of around 400 MPa, a yield strength of 250 MPa, and an elongation of 16-22%.
The mechanical properties of the SAE J404 87L20 steel are as follows:
| YieldRp0.2 | ≤ 714 (MPa) |
| TeileRm | ≤ 983 (MPa) |
| ImpactKV/Ku | 21(J) |
| ElongationA | 24% |
| Reduction in cross section on fractureZ | 23% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 223 |
SAE J404 87L20 Material Thermal Properties
The thermal performance parameters of the SAE J404 87L20 steel are as follows:
| Temperature (°C) | 22 | 823 | 862 |
| Modulus of elasticity (GPa) | - | 751 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 11 |
| Thermal conductivity (W/m·°C) | - | 14.3 | 11.2 |
| Specific thermal capacity (J/kg·°C) | - | 424 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.32 | - | - |
| Deity (kg/dm³) | - | - | 223 |
| Poisson’s coefficient, ν | - | - | 144 |
SAE J404 87L20 Material Machining Technology
SAE J404 87L20 steel is a medium carbon steel that contains up to 0.55% carbon, 0.30% manganese and 0.80% silicon. It is known for its high hardenability, being able to attain very high Rockwell hardness ratings of up to 62 HRC – making it a particularly hard and difficult material to machine. Furthermore, although SAE J404 87L20 steel is a hard material, it is also a highly ductile one with excellent formability. As a result, it is a popular choice of material across several industries, including automotive, aerospace, and medical.