precision forging S20C carbon steel forgings

precision forging S20C carbon steel forgings

S20C is a kind of steel, belonging to low carbon carbon steel.

JIS G4051-2005

S20C is a high-quality carbon structural steel material of Japanese JIS standard.

It is equivalent to my country's high-quality carbon structural steel 20# steel, and is generally replaced by my country's high-quality carbon structural steel 20# steel. If there is no special requirement, it is no problem to use 45# steel instead.

●Chemical composition:

Carbon C: 0.38～0.45

Silicon Si: 0.17～0.37

Manganese Mn: 0.50～0.80

Sulfur S: Allowable residual content ≤0.035

Phosphorus P: Allowable residual content ≤0.035

Chromium Cr: 0.90～1.20

Nickel Ni: Allowable residual content ≤0.030

Copper Cu: Allowable residual content ≤0.030

Molybdenum Mo: 0.15～0.25

●Mechanical properties:

Tensile strength b (MPa): ≥1080(110)

Yield strength s (MPa): ≥930(95)

Elongation 5 (%): ≥12

Shrinkage of area (%): ≥45

Impact energy Akv (J): ≥63

Impact toughness kv (J/cm2): ≥78(8)

Hardness ：≤217HB

Specimen size: The specimen blank size is 25mm

S20C refers to the carbon content, which is 0.2%, belonging to low carbon steel.

Steel can be divided into low carbon steel, medium carbon steel and high carbon steel.

Low carbon steel--the carbon content is generally less than 0.25%;

Medium carbon steel--the carbon content is generally between 0.25 and 0.60%;

High carbon steel--the carbon content is generally greater than 0.60%.

In addition to carbon (C) elements and a certain amount of silicon (Si) (generally not more than 0.40%) and manganese (Mn) (generally not more than 0.80%, as high as 1.20%) alloy elements for deoxidation, steel does not contain other alloy elements (except residual elements).

Steel with a carbon content of less than 2.1% is steel, and steel with a carbon content of more than 2.1% is iron.

The higher the carbon content in steel, the worse its toughness, and the higher the carbon content in steel, the better its toughness.

(1) Characteristics This steel is a high-quality low-carbon steel, cold extruded, deep-hardened steel. This steel has low strength, good toughness, plasticity and weldability. The tensile strength is 253-500MPa, and the elongation is ≥24%.

Normalizing can promote the spheroidization of the steel, refine the large proeutectoid ferrite, and improve the cutting performance of the blank less than 160HBS.

The process route of the steel mold parts is: cutting → forging mold → annealing → mechanical rough processing → cold extrusion molding → recrystallization annealing → mechanical finishing → carburizing → quenching, tempering → grinding and polishing → assembly.

(2) Supply status and hardness Unheat treated state, hardness ≤156HBS.

(3) Chemical composition of standard JB/T 6057-92 steel (mass fraction, %) C 0.17~0.23, Si 0.17~0.37, Mn 0.35~0.65, P≤0.035, S≤0.035, Ni≤0.30, Cr≤0.15, Cu≤0.25.

(4) Reference corresponding steel grades my country's GB/JB standard steel grade is 20, Taiwan's CNS standard steel grade S20C, Germany's DIN standard material number 1.0402, Germany's DIN standard steel grade CK22/C22, Britain's BS standard steel grade IC22, France's AFNOR standard steel grade CC20, France's NF standard steel grade C22, Italy's UNI standard steel grade C20/C21, Belgium's NBN standard steel grade C25-1, Sweden's SS standard steel grade 1450, Spain's UNE standard steel grade F.112, the United States' AISI/SAE standard steel grade 1020, Japan's JIS standard steel grade S20C/S22C.

(5) Phase change point temperature (approximate value) Ac1=735℃, Ac3=855℃, Ar3=835℃, Ar1=680℃

(6) Normalizing specification Temperature 920~950℃, air cooling after furnace exit. Hardness 131~156HBS.

(7) Specifications for softening treatment of cold pressed blanks Temperature 700~720℃, holding time 8~15h, then cooling at a cooling rate of 50~100℃/h, cooling with the furnace to ≤550~600℃, and air cooling after leaving the furnace.

Hardness before treatment ≤143HBS, hardness after softening ≤131HBS.

(8) Quenching specifications Temperature 910℃10℃, cooling with 10%NaCl brine.

Qinhuangdao Zhongwei Precision Machinery Co., Ltd. was established in 1997. It is a professional manufacturer of blank forgings engaged in the manufacture and processing of automotive parts, marine gearbox accessories, and engineering machinery accessories. It can forge copper alloys, titanium alloys, aluminum alloys, carbon steel, stainless steel, high-temperature alloys and other materials. The company covers an area of ​​more than 10,000 square meters and a standard factory building of 5,000 square meters. It has a complete set of advanced production technologies and equipment from mold design, development, parts manufacturing and processing. It has several die forging production lines, mainly 4000T, 2500T, 1600T, 1000T, and several auxiliary production lines. The annual output is 15,000 tons. It is exported to more than 20 countries and regions including Germany, the United States, the United Kingdom, France, Russia, etc.