Using a significance level of .05, apply Tukey’s method to the data of Exercise 12. Is there a pulse current that seems to be the best choice to yield maximum average toughness?
Super duplex stainless steels (SDSS) are ironbased alloys that offer an excellent combination of toughness and mechanical strength. Such alloys are useful for many applications in the chemical and petrochemical industries. Recent research has shown that the pulsed current gas tungsten arc welding (PCGTAW) process offers superior SDSS welds compared to other methods. The authors of “Optimization of Experimental Conditions of the Pulsed Current GTAW Parameters for Mechanical Properties of SDSS UNS S32760 Welds Based on the Taguchi Design Method” (J. of the Air and Waste Mgmt. Assoc., 2012: 1978–1988) researched the impact of different PCGTAW process parameters on mechanical properties of the welds of a particular SDSS. One investigation focused on seeing how pulse current (A) of the PCGTAW affects the toughness (J) of the SDSS welds. Here are experimental results for toughness measurements under three pulse current settings:
Use .05 to conduct the test for whether there are any differences in the true average weld toughness that may be attributable to the different pulse currents.