1144 stressproof

[colar]

Has anybody ever had experience using 1144 stressproof as an axle. I would like to economically increase the strength of our C1045 CR axles. 1144 is an alternative. I have heard some concerns abut "11" series steels having poor fatigue properties. These would be fixed axles (spindles) used on an agricultural implement.

 

[NtheTrenches]

I work for a small manufacturer of relatively large ag and construction equipment, and we have used stressproof considerably in the past. I'm not certain about the fatigue properties of stressproof, but I can tell you that I havn't seen a failure of this type in any of our applications. However, we do not use stressproof for any large axles. For our large axles we either use 1045CR or 4130 Heat Treated, due to the convenience of welding.

I can tell you that it has poor welding properties, so any coupling to a shaft or axle needs to be done by other means. It is however a low cost, high strength material.

 

Technically there is a difference between stressproof and just plain 1144. If you are going to be using it for axles, drivelines, transmission shafting etc, be sure to specify stressproof. It is actually a commercial trademark name, but all mills have their version of "stressproof", all based on the 1144 base material and then thermally treated. It is an excellent material, all the way around. It has higher machineability, stiffness, tensile yield, and ultimate tensile than 1045 and 4140 in their NORMAL states. I have found it to be weldable in most situations. Check with a good metallurgist to prevent weld related problems for your specific application.