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Hot isostatic pressing is to be used to produce the femoral head components of hip implants made from a novel grade of zirconia. A series of manufacturing trials have demonstrated that the processing route results in post-sintered surface features 43-107 m (mean 74m ) in size. In clinical use it is anticipated that the femoral heads will be loaded to maximum stress level of 50% of its tensile strength once implanted. What is the critical flaw size when in service and will the implant require polishing for it to withstand loading during clinical use? Where: - You may assume a value of 1.4 for Y - The grade of zirconia has a Tensile strength of 980MPa and a fracture toughness of 11 MPa.m 0.5 Select one or more: a. No b. 163.6m c. Yes d. 81.8m e. 20.5m f. 40.9m Hot isostatic pressing is to be used to produce the femoral head components of hip implants made from a novel grade of zirconia. A series of manufacturing trials have demonstrated that the processing route results in post-sintered surface features 43-107 m (mean 74m ) in size. In clinical use it is anticipated that the femoral heads will be loaded to maximum stress level of 50% of its tensile strength once implanted. What is the critical flaw size when in service and will the implant require polishing for it to withstand loading during clinical use? Where: - You may assume a value of 1.4 for Y - The grade of zirconia has a Tensile strength of 980MPa and a fracture toughness of 11 MPa.m 0.5 Select one or more: a. No b. 163.6m c. Yes d. 81.8m e. 20.5m f. 40.9m