The use of coated cutting tools to machine various materials is considered state-of-the art technology. The impact

Question:

The use of coated cutting tools to machine various materials is considered state-of-the art technology. The impact of cutting tool coating and material on cutting force was investigated in an article published in the International Journal of Engineering and Applied Sciences (Vol. 7, 2011). Five different steel cutting tool materials were compared: (1) uncoated CBN-High, (2) CBN-High coated with TiN alloy, (3) CBN-Low coated with TiN alloy, (4) CBN-Low coated with TiAIN alloy, and (5) mixed ceramic. Each cutting tool was run at three different speeds—100, 140, and 200 meters per minute—and two observations on cutting feed force (Newtons) were obtained for each run. The data (simulated from information provided in the journal article) are shown in the table. The objective of the experiment is to assess the impact of cutting tool type and cutting speed on feed force.

a. For this study, identify the experimental design, factors, treatments, experimental units, and response variable.

b. Give the equation of the complete model for analyzing the data.

c. In terms of the model parameters, what null hypothesis would you test to determine whether the impact of cutting tool on feed force depends on cutting speed.

d. Use regression to carry out the test, part c. What do you conclude?

e. An SPSS printout of the ANOVA of the data is displayed below. Verify that the test results, part d, agree with the information provided on the printout.

f. Do you recommend conducting tests for main effects? Why or why not?