The Crack Length Growth – A Fracture Parameter in a Stainless Steel Influenced by the Loading Test

Abstract:

The defects or micro-cracks that exist in a product mass from the elaboration phase, can extend controlled or not, because of a variable solicitation applied to a product or a sample. The Fracture Mechanics parameter that highlight the crack propagation in time is its rate growth marked as da/dN and represents the crack advancement length during a solicitation cycle. This can be studied based on some mathematical models obtained from some propose models, experimentally determined. In this paper, a propagation process analysis is made of a fracture crack by an axial-eccentric fatigue loading for a 10TiNiCr175 stainless steel. CT type flat samples were loaded with an asymmetry coefficient R= 0.3, for the solicitation temperatures: T= 293K (20°C), T= 253K (-20°C), respectively T= 213 K (-60°C). The crack growth increase was studied by three most used mathematical models: the polynomial method standardized according to ASTM E647, method proposed by Paris and method proposed by Walker.

• Periodical: Applied Mechanics and Materials (Volume 823)
• Pages: 489-494
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.823.489
• Online since: January 2016
• Authors: Valcu Roşca*, Cosmin Mihai Miriţoiu
• Keywords: Asymmetry Coefficient, Crack, Cracking Rate, Solicitation Cycle, Stress Intensity Factor (SIF)

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