UNITED STATES
(English)
country:
UNITED STATES
language:
English
Italiano
Choose your country
join us
Reserved Area
Accreditation
Company
Company
Mission & vision
Our story
Our values
TEC Eurolab Board
Network
tec eurolab & kaizen
Corporate responsability
Services
Non-destructive testing
R&D
Certification
Inspection
Training
Sectors
Automotive & Racing
Aerospace & Defense
Manufacturing
Biomedical
Electronic
Topics
Additive manufacturing
Composites
Fasteners
Paints & coatings
Failure analysis
Welding
ROHS
News and Events
News and events
Case study
Contact us
Contact us
Labs location
TEC Eurolab Newsletter
Careers
›
‹
Glossary of terms
>
Temporary distorsion
Temporary distorsion
Also serious is the permanent distortion that results from yielding during service, from creep, and from buckling (or compression instability).
Yielding during service. If a part yields or distorts permanently during service after one or more load applications, the stress on the part has obviously exceeded the yield strength (actually, the elastic limit). If the part is a spring, we say that the spring has "taken a set," indicating that the spring is permanently distorted and can no longer perform its intended function. Identification of this type of failure is quite simple and obvious.
Less simple and obvious, however, may be the means for correcting the problem so that the same type of failure will not occur on other similar springs. In performing this function, the analyst will be tried to the limit of his or her ability - for tracking down the specific cause of yielding really becomes a challenge. It is vital to learn, for example, if this yielding is an isolated problem or is occurring on similar parts. If it is isolated, it is necessary to learn the details of what occurred to make this specific part yield. Obviously, it is necessary to measure the distorted spring and compare it with a new spring of the same original dimensions. Photographic comparisons are often useful with the new and yielded parts in the same photograph with a scale, if necessary, to show the distortion.
Detailed study of the part from a metallurgical standpoint is essential, with attention to such questions as the following: Is the microstructure the same as was originally specified, or has it been altered by exposure to an elevated temperature? Has the hardness been reduced by tempering during service? If so, what temperature would have caused that reduction in hardness level? Was the temperature abnormally high for the application? If so, why?
If investigation indicates that this is only one instance of a general and widespread problem, it may be necessary to redesign the assembly to reduce the stresses and temperatures, or to obtain a material with a higher yield strength at the operating temperature.
previous:
Temper brittleness
next:
Tensile strength
Glossary of terms
Our team of experts is ready to help you test and improve materials, products and processes.
Send us your request
TEC Eurolab Srl
- Viale Europa, 40 - 41011 Campogalliano (Mo) - Italy
Tel:
+39 059 527775 -
Fax:
+39 059 527773 -
Email:
info@tec-eurolab.com
VAT
e
C.F
02452540368
Share on:
Tag directory
Site map
Top searches
Utility
Glossary
Download contents
Copyright © 2005-2021 TEC Eurolab Srl
[ Privacy Policy ]
[ Privacy information ]
[ Cookie policy information ]
[ Legal ]
[ Terms of sale ]
Contact us
to learn more or request your tomographic analysis
click here
X