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Crack paths under both fatigue and fracture conditions are governed by thecrack tip displacement field and the material deformation characteristics, including thoseinfluenced by metallurgical anisotropy. Experimental techniques such as thermoelasticityand photoelasticity have been successfully used to characterise the elastic stress fieldsaround cracks but they do not take into account either plasticity or anisotropy.Considerable work has been carried out to characterise crack tip stress fields fromdisplacement measurements. The current method of choice for obtaining displacement fielddata is digital image correlation (DIC). This technique has recently been extended todetermine T-stresses in cracked specimens. Full field displacement techniques also have theadvantage that the influence of crack tip plasticity may be evaluated directly. This paperdescribes the technique for obtaining T-stresses from displacement fields measured usingDIC. The algorithm used was based on Williams’ solution to obtain both K and the nonsingularterm T. Results have shown that the technique works well when compared withfinite element simulations. A significant amount of work was also carried out tocharacterise displacement fields around a crack during the steady state tearing undermonotonic load. The fracture parameter of interest was the crack tip opening angle(CTOA). Results from displacement field characterisation corresponded well to moreconventional techniques. It also showed clearly the effects of measurement length andposition on CTOA data.