Eq 1

where Pis the final density and rT is the theoretical density for the material. This assumes isotropic shrinkage in sintering. For example, if a 13.8 mm dimension shrinks to 12 mm, then the shrinkage factor is 0.13 or 13%, calculated as the change in a dimension divided by the original dimension. Because the target is the final component size, each dimension of the tool cavity is oversized to accommodate shrinkage. If the desired final dimension is Zf at a fractional density P/PT from a feedstock with a fractional solids content of 0, then the initial dimension of the tooling is given in terms of the tool cavity expansion factor, Z:

0 0

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