Roy Lobenhofer

a k a Lobenhofer Consulting, Inc.

Tensile Properties

The lack of attention paid to the control of tensile properties of gray and ductile iron by foundries has been a great source of irritation to me for some time. It is only exceeded by my aggravation with purchasers of iron castings not paying attention to how well their suppliers are assuring they are getting what they are ordering.

In many respects a catch-22 situation has arisen. Designers use gigantic safety factors when considering the properties of iron castings because they have found foundries do not control the properties. Conversely, foundries don’t worry about controlling the properties because they “know” such huge safety factors are used. Of course, my irritation is raised even higher when I have to listen to people trying to increase the iron casting market complain about designers not using the capabilities of the irons.

This isn’t a new problem. It has been around as long as I’ve been connected with the foundry industry. Yes, I’ve listened to many arguments concerning the inadvisability of using tensile properties as a purchasing criteria. Some of the arguments may have validity, but until foundries learn to control tensile properties, I don’t think we can expect designers to depend on foundries to control more esoteric properties.

To address my frustration on this topic I have started a three pronged attack. The first was to write a piece of software, I have named “Predict” to assist in controlling tensile properties.

The second prong is to write or find articles dealing with Controlling Tensile Properties.

The final prong is to offer provide an analysis of any foundry's control of their tensile properties at no charge. Click on this to find out how.