Common structural steel in Japanese steel (JIS series) grades mainly consists of three parts:
The first part represents the material, such as: S (Steel) represents steel, F (Ferrum) represents iron;
The second part represents different shapes, types, and uses,
For example: P (Plate) means plate, T (Tube) means tube, K (Kogu) means tool;
The third part represents the characteristic number, generally the minimum tensile strength.
For example: SS400 - the first S represents steel, the second S represents "structure", 400 is the lower limit tensile strength of 400MPa, and the overall represents ordinary structural steel with a tensile strength of 400MPa.
SPHC - The first S is the abbreviation of Steel, P is the abbreviation of Plate, H is the abbreviation of Heat, and C is the abbreviation of Commercial. The overall representation generally uses hot-rolled steel plates and steel strips.
SPHD--represents hot-rolled steel plates and strips for stamping.
SPHE--represents hot-rolled steel plates and strips for deep drawing.
SPCC - represents generally used cold-rolled carbon steel sheets and strips, equivalent to China's Q195-215A grade. The third letter C is the abbreviation of Cold. When it is necessary to ensure the tensile test, add T at the end of the grade to indicate SPCCT.
SPCD - represents cold-rolled carbon steel sheets and strips for stamping, equivalent to China's 08AL (13237) high-quality carbon structural steel.
SPCE - represents cold-rolled carbon steel sheets and strips for deep drawing, equivalent to China's 08AL (5213) deep drawing steel. When non-timeliness needs to be ensured, add N to the end of the grade to indicate SPCEN.
Quenching and tempering codes of cold-rolled carbon steel sheets and steel strips: annealed state is A, standard quenching and tempering is S, 1/8 hardness is 8, 1/4 hardness is 4, 1/2 hardness is 2, and hardness is 1.
Surface processing code: D for matte finish rolling and B for bright finish rolling. For example, SPCC-SD represents standard quenched and tempered, matte finish rolling, generally used cold-rolled carbon sheets. Another example is SPCCT-SB, which represents cold-rolled carbon sheets with standard tempering and bright processing, requiring guaranteed mechanical properties.
The JIS mechanical structure steel grade expression method is: S + carbon content + letter code (C, CK), in which the carbon content is expressed by the intermediate value × 100. The letter C: represents carbon. K: represents carburizing steel. For example, the carbon content of carbon rolled plate S20C is 0.18-0.23%.