precision forging SCr240 alloy steel forgings

precision forging SCr240 alloy steel forgings

Product details SCr240

Basic information 20Cr,

Low hardenability carburizing steel.

Unified digital code: A20202 Standard GB/T 3077-1999 GB/T 17107

Zhongwei precision service, quality first AISI 5120 JIS SCr240 GB

SCr240 Chemical composition

Carbon C: 0.18~0.24

Silicon Si: 0.17~0.37

Manganese Mn: 0.50~0.80

Chromium Cr: 0.70~1.00

Sulfur S:

Allowed residual content ≤0.035 Phosphorus P: Allowed residual content ≤0.035 Nickel Ni: Allowed residual content ≤0.030 Copper Cu: Allowed residual content ≤0.030

Mechanical properties

Heat treatment: First quenching heating temperature (℃): 880; Coolant: water, oil Second quenching heating temperature (℃): 780~820; Coolant: water, oil Tempering heating temperature (℃): 200; Coolant: water, air Tensile strength (σb/MPa): ≥835 Yield point (σs/MPa): ≥540 Elongation after fracture (δ5/%): ≥10 Section shrinkage (ψ/%): ≥40 Impact absorption energy (Aku2/J): ≥47 Brinell hardness (HBS100/3000) (annealing or high temperature tempering state): ≤179 Delivery status: delivered in heat treatment (normalizing, annealing or high temperature tempering) or non-heat treatment state, the delivery status should be indicated in the contract.

Application examples

This steel is mostly used to manufacture carburized parts (oil quenching) with high core strength requirements, surface wear, cross-sections below 30mm, or complex shapes and low loads, such as: machine tool gearbox gears, gear shafts, cams, worms, piston pins, claw clutches, etc.; for parts with small heat treatment deformation and high wear resistance, high-frequency surface quenching should be performed after carburizing, such as gears, shafts, spline shafts with a modulus less than 3. This steel can also be used in the quenched and tempered state to manufacture parts with high working speeds and medium impact loads. This steel can also be used as low-carbon martensitic quenching steel to further increase the yield strength and tensile strength of the steel (about 1.5~1.7 times).

Company introduction:

Qinhuangdao Zhongwei Precision Machinery Co., Ltd. was established in 1997 and is a professional manufacturer of rough forgings engaged in manufacturing and processing automotive parts, marine gearbox accessories, and engineering machinery accessories. The company can forge copper alloy, titanium alloy, aluminum alloy, carbon steel, stainless steel, high temperature alloy and other materials. The company covers an area of ​​more than 10,000 square meters, with a standard factory building of 5,000 square meters. It has a complete set of advanced production technology and equipment from mold design, development, parts manufacturing and processing. It has multiple die forging production lines mainly based on 4000T, 2500T, 1600T, 1000T, and multiple 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.