SPCC is well-known in the steel industry. But for the many little brothers with suffixes in SPCC, many friends may only know their names but not recognize them. Today, let’s sort out these little brothers of SPCC.
1.SPCCDT
Source of brand: Elevator plate technical agreement.
Suffix explanation: DT—for elevators.
The main difference from ordinary SPCC: the plate shape accuracy is good, and the general requirement is advanced precision PF.B, while the ordinary SPCC generally requires ordinary precision PF.A. See warranty below.
The following are some of the requirements of a certain standard for SPCCDT:
1) Unevenness ≤ 4mm (normally 8-17mm), diagonal tolerance ≤ 2mm, sickle bend ≤ 3mm/2m (normally 6mm/2m);
2) For chemical composition, mechanical properties, and others, please refer to the SPCC regulations in BQB408.
2.SPCC-SD
Source of brand name: Enterprise standards of various steel mills.
Explanation of suffix: S - annealing + smoothing, D - pitted surface.
The main difference from ordinary SPCC: generally no difference.
3.SPCC-SB
Source of brand name: a technical agreement for electronic components.
Explanation of suffix: S—annealed + flattened, B—glossy.
The main difference from ordinary SPCC is that the surface structure is smooth.
The following are some requirements of a certain standard for SPCC-SB:
1) Surface roughness requirement Ra≤0.2μm, thickness tolerance ≤±0.01mm. That is, the surface requires smooth surface and high thickness accuracy;
2) Tensile strength is 400-620MPa, hardness HR30T is 70±5.
4.SPCC-HS
Source of grade: Technical Agreement on Steel for Welding Wire.
Explanation of suffix: HS—for welding wire.
The main difference from ordinary SPCC is: there are hardness requirements; there are requirements for yield strength.
The following are some requirements of a certain standard for SPCC-HS:
1) Hardness HRB requirement is 35-55;
2) The yield strength requirement is 160-240MPa.
5.SPCC-YT
Source of brand name: Oil Drum Board Technical Agreement.
Explanation of suffix: YT—for oil drums.
The main difference from ordinary SPCC: there are requirements for yield strength.
The following are some requirements of a certain standard for SPCC-YT:
The yield strength is required to be above 170MPa.
6.SPCC-MB
Source of grade: Technical agreement on steel for door panels.
Explanation of suffix: MB - for door panels, the B here does not mean smooth.
The main difference from ordinary SPCC is: good plate shape accuracy.
The following are some of the requirements of a certain standard for SPCC-MB:
Roughness: ≤5mm; Yield strength ≤220MPa.
7. SPCC-1D, SPCC-4B, SPCC-8D
Source of brand name: Japanese Industrial Standard JIS G3141.
Explanation of suffix: 1 - fully hard state, not annealed; 4 - 1/4 hard state, incomplete annealing at low temperature;
8-1/8 hard state, also after incomplete annealing. Annealing completeness increases from 1 to 8.
The main differences from ordinary SPCC:
Because it is produced by low-temperature annealing, the material is not completely recrystallized, and the unrecrystallized structure will play a certain strengthening role. However, using unrecrystallized structures to increase strength sacrifices shaping and toughness. If ordered according to JIS standards, these three grades do not guarantee tensile properties, only hardness. Therefore, it can generally only be used to produce relatively simple parts, such as electrical cabinet slide rails and other parts, and is not suitable for stamping.
