Understand the Life prediction of your Design – SOLIDWORKS Simulation

 

 

In day to day life, we are seeing  limitation of time, business hours has 8-10 hrs., if you stretch for 2 more hours will lead to tired but somebody will not feel the same. Likewise all Engineering Materials has its own limitation with stress and duration of loading. Some of the material has more strength but most of the material will not stretch for a while. A small change in duration with load will causes problem.

We may face Design failure during the work scenario sequence of our product. To avoid those issues and update with confident to say about product life before you manufacture which gives you greater confidence in performing the same after conducting of cycle test will lead to save a lot which addresses the Critical Technical Issues.

The below mentioned figure shows that process of Finite Element Analysis which has done by SIM Technologies before a decades ago, as SOLIDWORKS reseller in Chennai and Coimbatore . We are serving with many Industries based on different verticals supported by us.

Process of Validation

FEA is tool will helps us to understand the product behavior before manufacture and validate your product / component with more strength. The above Figure 1 depicts the workflow of the FEA which can be a static, Thermal, Nonlinear and Linear Dynamic combinations of two or more than three will follows the same procedure. Once carried away from this kind of analysis using the S-N curves for material will decide the stress Vs No of cycles withstand for the loading condition. This loading condition can be mechanical loading, (Live load, Dead load) or Thermal loading (conduction, convection, Radiation).

The analysis which has no of cycles and stress induced in the product and interaction with constant amplitude event or may variable amplitude can be analyzed using the test data with mean stress correction.

For Ductile materials, Gerber method will be followed with mean stress correction if Brittle materials is employed in the analysis we need to use Goodman method and Soderberg is more conservative method compared with other two methods.

Factors that Affect Fatigue Life

A standardized, fully reversed fatigue test is used to determine a base-line E-N relationship for a polished specimen, approximately 6 mm in diameter. While the fatigue or endurance limit measured in this test is denoted by ε’ea component in service has lower limit, εe that reflects modifications to a specimen outside of the laboratory. For steels in particular, several empirical relationships account for the variation in εe as a result of the following:

  • Component size, Csize
  • The type of loading, Cload
  • The effect of notches, Cnotch
  • The effect of surface finish, Csur < 1 (promotes crack growth)
  • The effect of surface treatment, Csur >1 (inhibits crack growth)

To account for these effects, specific modifying factors are typically applied to the test result so that:

εe =ε’eCnotchCsizeCloadCsur . . .

Where reciprocal of the product, CnotchCsizeCloadCsur , is collectively known as the fatigue strength reduction factor Kf:

Kf = 1 / (CnotchCsizeCloadCsur . . .)

It is very important to remember that all the modification factors are empirical, conservative and generally only applicable to steel. They provide little or no fundamental insight into the fatigue process itself other than providing approximate trends. In particular they should not be used in areas outside their measured applicability.

Design for Strength: Traditionally in failure analysis, designers consider the ultimate strength of their components; but in-service load is rarely static in nature as there is usually a cyclical variation.

 

Design for Life: Adding this approach, you can utilize finite element analysis (FEA) to predict and address causes of failure.

 

Being technical front runners, we need to provide better product to serve the customers. In SOLIDWORKS simulation we have solution for life time estimation of your component with the support of SIMTEK Authorized SOLIDWORKS Simulation Reseller located at Chennai, Kolhapur, New Delhi, Banglore. For more details log on to www.simtek.in | call: 8754447021 | email: info@simtek.in