Hot Rolled AISI 4140 Alloy Mould Steel/DIN 1.7225 Special Steel Bars

AISI 4140 Product Introduction

4140 steel has high strength, hardenability, good toughness, small deformation during quenching, 

and high creep strength and durable strength at high temperature. It is used to manufacture forgings 

requiring higher strength and larger quenched cross section than 35CrMo steel, such as large locomotive 

traction gear, supercharger transmission gear, rear axle, highly loaded connecting rod and spring clip, and 

can also be used for oil drilling.

4140 Steel Equivalent Steel Grade 

AISI 4140 Chemical Composition

SAE 4140 Mechanical Properties

ASTM 4140 Surface Treatment and Heat Treatment

1.Surface Treatment

Plate: Origin Black, Orign cold rolled bright, Machined, Grinded

Bar:  Origin Black, Orign cold rolled(drawn) bright, Turned, Peeled, Grinded

2.Heat treatment 

Heat treatment standard: quenching at 850℃, oil cooling; tempering at 560℃, water cooling, oil cooling;

1) Forging

Preheat the steel carefully, then raise the temperature to 1150-1200°C for forging. Do not forge below 850°C.

2)Annealing

Heat the AISI 4140 slowly to 800-850°C and allow enough time for the steel to be thoroughly heated. Cool slowly in the furnace to 480°C followed by air cooling.

3)Stress Relieving

When parts are heavily machined, ground or otherwise subject to cold work, stress relieving will be beneficial prior to hardening.

4)Hardening

AISI 4140 steel is usually supplied ready heat treated to 18-22HRC. If further heat treatment is required annealed AISI 4140 should be heated slowly to 840-875°C and after adequate soaking at this temperature quench in oil. Temper as soon as the tools reach room temperature.

5)Tempering

Heat the AISI 4140 carefully to a suitable temperature selected by reference to a tempering chart or table (usually between 550-700°C, soak at the temperature for 2 hours per 25mm of ruling section, then allow to cool in air. Tempering between 250-375°C is not advised as tempering within this range will seriously reduce the impact value.

4140 Steel Applications

It is used to manufacture forgings that require higher strength and larger quenched and tempered sections than 35CrMo steel, such as large gears for locomotive traction, supercharger transmission gears, rear axles, connecting rods and spring clips that are heavily loaded, and can also be used for Drill pipe joints and fishing tools for oil wells below 2000m, and can be used for molds of bending machines, etc.

G41400 Steel Product Photo

Company Introduction

    Dongguan Songshun Mould Steel Co., Ltd. is an Indusrtial and trading company with 2 warehouses that manufactures good & high quality kinds of steels starting from 2012. The company provides the customized products and OEM service. What´s more, we keep the mass stock of over 20000 tons. In those years, we offer 

a wide range of steels to our customers from all over the world. And we enjoy high praise among them.

Customer Photos

     We warmly welcome new and old customers to establish good and long term relationship with us based on equality and mutual assistance.

Certifications

Product packaging

FAQ

Q:Are you a factory or a trading company?

A: The fact is that we are a company. We have own factory and several warehouses. Under the trend of globalization of the world, we established a professional foreign trade department to change the world.

Q: What is your delivery date?

A: The delivery date is about 10-30 days after receipt of payment.

Q: Can I get some samples?

A: We are honored to offer you samples.

Q: What port do you usually ship from?

A: We have 3 common ports,Tianjin, Shanghai and Shen.

Q: What is the payment terms?

A: T/T is our priority, L/C is also OK for us.

Contact us

Feel free to contact us,we are glad to serve for you.

Songshun Always Open the Door for You.

MiKi Zhuo

ADD:No.4 Dongda Street, Shatou, Changan Town, Dongguan City, Guangdong Province, P.R.C China

For more 4140 steel product information, please click this link:

https://songshunsteel.en.china.cn/2194011-4140-Steel-Bar