(1) A ceramic with KIc = 4 MPa m1/2 contains pores with radius a = 5 µm due to incomplete sintering. These pores lead to a decrease in the failure stress of the material in both tension and compression. One in every ten grain boundary junctions contains a void; the grain size of the ceramic is 50 µm. The ceramic fails in compression when the length ℓ of each crack generated at the voids equals one-half of the spacing between the voids. (a) Determine the compression strength of the ceramic, using the equation from Sammis and Ashby. (b) Determine the tensile strength of the ceramic, assuming flaws with size a (2) (a) Calculate the compressive strength for a ceramic containing crack of size 100 µm. Let μ be the coefficient of friction between the flaw walls and be the length of the cracks generated at the ends of an existing flaw. Assume that the onset of failure corresponds to a value of ℓ= 2a and that μ = 1, and that KIc = 4 MN m1/2. (b) Compare the tensile strength with the compressive strength that you obtained in part (a)