Structural Relaxation Due to Creep Impacts Performance

Consider the impact of structural relaxation

Many engineering structures must be designed to operate successfully in hostile thermal environments. Pipe hangers supporting hot and heavy steam lines, aircraft engine blades, and injection molding machine components are just a few examples. When designing such mechanical systems, it is wise to consider the impact that structural relaxation due to creep might have on long-term performance.

Creep is a thermally induced phenomenon that typically occurs in crystalline structures, like metals. Its effects, as observed on a macroscopic level, are caused by the diffusional flow of vacancies and dislocations on a microscopic level within the crystalline structure. These vacancies are point defects, and they tend to favor grain boundaries that are normal, rather than parallel, to the applied stress. Their movement tends to be from regions of high concentration to regions of low concentration. Dislocations in grains are line defects. Their movement tends to be activated by high stresses, although this may also occur at intermediate temperatures. Grain boundary sliding is sometimes considered as a separate mechanism that also contributes to creep deformation. Continue reading

ANSYS Events, Webinars and Workshops This Week – April 30 to May 4

image of Learning text on a keyboardToday kicks off the Offshore Technology Conference (OTC), the world’s foremost event for the development of offshore resources in the fields of drilling, exploration, production, and environmental protection. If you’re attending, please do stop by our Booth 5001 and say hello!

Our Ask-the-Expert series continues with two webinars on Wednesday. Register for one or both.

There are also three Confidence By Design Workshops this week, so make sure you sign-up to attend. You’ll find these in Denver, Orlando and Salt Lake City, more details below. Continue reading