Plackett-Burman Designs

Experimental Objective

A quality engineer wants to increase the lifetime of weld-repaired die castings. The engineer is interested in all factors that influence the lifetime of the die castings. Eight factors, shown in Table 6.1, are suspected to have some influence on the lifetime of the castings. Since runs are expensive, a Plackett-Burman design is used for the experiment.

Table 6.1: Factors for Die-Cast Fatigue Experiment

Type	Name	-1 level	level	Description
Factor	INITSTR	no treat	treat	Initial structure
	BEADSIZE	small	large	Bead size
	PTREAT	none	HIP	Pressure treatment
	HTREAT	anneal	solution	Heat treatment
	HOLDTIME	30 sec	600 sec	Holding time
	CRATE	slow	rapid	Cooling rate
	POLISH	chem	mech	Polishing method
	FTREAT	none	peen	Final treatment
Response	LIFETIME			Casting lifetime

The goal of the experiment is to identify the factors that have a significant influence on die-cast lifetime.

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Task List