In a small-disc test a small, disc-shaped portion of a component is loaded until failure. The article Optimizing the Sensitivity of the Small-Disc Creep Test

In a small-disc test a small, disc-shaped portion of a component is loaded until failure. The article €œOptimizing the Sensitivity of the Small-Disc Creep Test to Damage and Test Conditions€ (M. Evans and D.Wang, J. Strain Analysis, 2007:389€“413) presents the results of a factorial experiment to estimate the effects of properties of the disc on the time to failure (in ms). The data in the following table are presented as a 2⁵design. The factors are A: hole diameter, B: disc diameter, C: disc thickness, D: punch head radius, and E: friction coefficient. Two other factors discussed in the article are not considered here.

a. Compute estimates of the main effects and the interactions.

b. If you were to design a follow-up experiment, which factors would you focus on? Why?

Treatment Outcome Treatment Outcome Treatment Outcome Treatment Outcome 1 2486.8 d 2912.3 e 2508.6 de 2915.0 ad 1319.4 2446.8 1328.1 1507.2 ade 1536.7 ae be a b 2470.2 bd 2885.3 bde 2872.8 ab 1303.2 abe abd cd cd bcd abcd 1491.8 7723.0 1303.3 6864.7 abde cde 1477.9 7731.6 6817.4 3845.2 4289.3 3875.0 acde 4345.1 7045.1 bcde abcde bc 7952.8 bce 6994.2 7969.1 abc 3992.2 4505.5 abce 3961.2 4494.5