Mesh monitor casting of Ni-Cr alloys: element effects

A mesh monitor has previously been used for quantitative evaluation of the casting of dental alloys. A castability value, Cv was defined. For curve-fitting, a transformed castability value, Cv,t, was used. A series of alloys was selected so that effects of major elements on Cv, t and, hence, on Cv could be determined. Compositions were chosen so that correlated effects would be avoided. Assuming a linear dependence on the concentrations of individual elements, one may use the following equation to describe Cv,t: (Formula: see text) where each term employs an elemental concentration in weight percent, (Ei), and a coefficient, Ki, for the ith term. Because Ei's are constant for each alloy, Ki = fi (TA, TM) = gi (TC, TM). The temperature-dependent coefficients, Ki, were determined for seven elements and for the (Ni/(Cr) ratio. It was also found that Si and Be produce a synergistic effect. The results help our understanding of the casting behavior of Ni-Cr dental alloys; this approach may be useful in the design of dental alloys.