A mechanistic understanding of fracture in human bone is critical to predicting fracture risk associated with age and disease. Despite extensive work, a mechanistic framework for describing how the underlying microstructure affects the failure mode in bone is lacking.

/pdf/mechanistic-fracture-criteria-for-the-failure-of-human-4hekqdriot.pdf

Mechanistic fracture criteria for the failure of human cortical bone

https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1048&context=usnavyresearch

Review of fracture toughness (G, K, J, CTOD, CTOA) testing and standardization

http://matrix.seas.ucla.edu/papers/2000/s-NG-operating.pdf

Operating temperature windows for fusion reactor structural materials

https://digital.library.unt.edu/ark:/67531/metadc926677/m2/1/high_res_d/961528.pdf

Grain-boundary engineering markedly reduces susceptibility to intergranular hydrogen embrittlement in metallic materials

Many manufacturing processes can induce residual stresses in components. These residual stresses influence the mean stress during cyclic loading and so can influence the fatigue life. However, the initial residual stresses induced during manufacturing may not remain stable during the fatigue life. This paper provides a broad and extensive literature survey addressing the stability of surface and near-surface residual stress fields during fatigue, including redistribution and relaxation due to static mechanical load, repeated cyclic loads, thermal exposure and crack extension. The implications of the initial and evolving residual stress state for fatigue behaviour and life prediction are addressed, with special attention to fatigue crack growth. This survey is not a critical analysis; no detailed attempt is made to evaluate the relative merits of the different explanations and models proposed, to propose new explanations or models or to provide quantitative conclusions. Primary attention is given to the residual stresses resulting from four major classes of manufacturing operations: shot peening and related surface treatments, cold expansion of holes, welding and machining.

A literature survey on the stability and significance of residual stresses during fatigue

A procedure to determine the ductile fracture toughness value JIc, the value of the J integral at incipient crack growth, is described. The procedure was developed by the working committee of ASTM Task Group E24.01.09 on Elastic-Plastic Fracture under Committee E-24 on Fracture Testing. The principal goal of this report is to present a procedure for JIc determination that may be used as a basis for an ASTM standard on elastic-plastic testing. Although this procedure is described in terms of the multiple-specimen technique, any single-specimen method can be used as long as a good correspondence exists between the crack extension as measured by the heat tinting technique and that measured by single-specimen methods.

A Procedure for the Determination of Ductile Fracture Toughness Values Using J Integral Techniques

An experimental method is described which can measure the direction and magnitude of residual and applied stress in metals. The method uses optical interference to measure the permanent surface deformation around a shallow spherical indentation in a polished area on the metal specimen. The deviation from circularly symmetrical surface deformations is measured at known values of applied stress in calibration specimens. This deviation from symmetry can then be used to determine the direction and magnitude of tensile residual stress in specimens of the same material. Determination of compressive residual stress is more limited.

Residual-stress measurement using surface displacements around an indentation

: Correction factors for crack shape and non-ideal material yielding are determined from various sources for the pressurized, autofrettaged tubes containing semi-elliptical cracks. These results are employed in the life prediction of pressurized thick tubes with straight-fronted and semi-circular cracks, for various amounts of autofrettage. Experimentally determined lifetimes for tubes having zero and 30 percent nominal overstrain are significantly greater than the predictions for both straight fronted and semi-circular cracks. This is related to multiple initiation and early growth of cracks from the notch. Experimentally determined lifetimes for a tube with a 60 percent nominal overstrain are somewhat less than predicted. This effect is partially explained by additional experimental work which shows that the angle of opening of rings cut from autofrettaged tubes is somewhat less than the ideal predictions.

Stress Intensity and Fatigue Crack Growth in a Pressurized, Autofrettaged Thick Cylinder

Thermomechanical modeling of transient thermal damage in cannon bore materials

: Load-line displacement information for the three-point bend specimen is presented and compared with information from the literature, with emphasis on the needs of those performing fracture tests.

John H. Underwood

Papers

A Procedure for the Determination of Ductile Fracture Toughness Values Using J Integral Techniques

Residual-stress measurement using surface displacements around an indentation

Stress Intensity and Fatigue Crack Growth in a Pressurized, Autofrettaged Thick Cylinder

Thermomechanical modeling of transient thermal damage in cannon bore materials

Compliance of a three-point bend specimen at load line