1.* b) You are working on a sodium ion conducting ceramic electrolyte that uses sodium metal as an electrode. Sodium interacts with the ceramic if the battery is not operated properly (black spots in left image) causing environmentally-assisted crack growth (illustrated above). You manufacture ten coupons that have surface aws (indicated as "notch\" in the picture on the top left). You apply uniform tensile stresses (yellow arrows) with no sodium metal present until fracture occurs. The strengths of the ten specimens are listed below. 150, 165, 192, 207, 217, 243, 257, 273, 287, 300 MPa Use the data above to construct a Weibull plot to determine So and m. You may assume that A, is equal to the surface area of the coupons, and that failure occurs because of the edge aws. (m=3.7, Sn = 257 MPa) Assuming that K; is given by the equation for edge flaws, and that K18 for this ceramic is equal to 1.4 MPa mm, calculate the size of the largest aw in the specimen that has the median strength (9.2 x 10'6 m) When used in a battery pack, failure occurs when the crack reaches a length of 1.0 x 10'5 m. Crack growth follows an equation given by % =1.0 XIO'GKP m/s (where K: is in MPaml'Z) t