crack length การใช้

• Beyond the critical Griffith crack length, the crack becomes dangerous.
• Second, the lever arm is getting longer with increased crack length a.
• During the pipeline inspection a crack length of 10 cm was revealed, through which ammonia had leaked.
• The measured crack length determines surface energy \ gamma in relation to a rectangular, beam-shaped specimen.
• The compliance is determined out of the crack length L, the width w and the beam thickness t.
• From the critical crack length a _ c an instable crack expansion and the destruction of the specimen is initiated.
• As the crack advances so " K " rises ( because crack length appears in the calculation of stress intensity ).
• In his third paper, Hall showed that the length of slip bands or crack lengths correspond to grain sizes and thus a relationship could be established between the two.
• One basic assumption in Irwin's linear elastic fracture mechanics is small scale yielding, the condition that the size of the plastic zone is small compared to the crack length.
• The critical crack length a _ c corresponds to the maximum force F _ { max } in a force-length-diagram and a minimum of the geometric function Y _ { MIN }.
• It is important to systematically check for possible stress concentrations caused by cracks there is a critical crack length of 2a for which, when this value is exceeded, the crack proceeds to definite catastrophic failure.
• Because the strain energy released is directly proportional to the square of the crack length, it is only when the crack is relatively short that its energy requirement for propagation exceeds the strain energy available to it.
• In addition, the measurement inaccuracy increases with a high surface fracture toughness resulting in a smaller crack length or broken wafers at the blade insertion as well as the influence of the fourth power of the measured crack length.
• In addition, the measurement inaccuracy increases with a high surface fracture toughness resulting in a smaller crack length or broken wafers at the blade insertion as well as the influence of the fourth power of the measured crack length.
• If a value of the minimum size crack length, " a ", is also selected, that allows the solution for " ? " the stress near the crack below which the component must be kept.
• Where a is the crack length and m is typically in the range 3 to 5 ( for metals ), which states that the rate of crack growth with respect to the cycles of load applied is a function of the stress intensity factor; this is named Paris'law.
• Where G is the strain energy release rate, \ sigma is the applied stress, a is half the crack length, and E is the Young s modulus, which for the case of plane strain should be divided by the plate stiffness factor ( 1-? ^ 2 ).
• This ultimate failure is definite since the crack will propagate on its own once the length is greater than 2a . ( There is no additional energy required to increase the crack length so the crack will continue to enlarge until the material fails . ) The origins of the value 2a can be understood through brittle fracture.
• Where c _ f \ approx half of the FPZ length, \ alpha _ 0 = a / D = relative initial crack length ( which is constant for geometrically similar scaling ); g ( \ alpha _ 0 ) = k ^ 2 ( \ alpha _ 0 ) = dimensionless energy release function of linear elastic fracture mechanics ( LEFM ), which brings about the effect of structure geometry; k ( \ alpha _ 0 ) = K ( \ alpha _ 0 ) b \ sqrt D / P, and K = stress intensity factor.