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After
passing metallurgical inspection, SSM feedstock is cut to the desired
shot weight (slugs) using high-speed band saws that ensure production
repeatability. Each slug is heated on a carousel indexing table, raising
the slug temperature to the SSM processing range. This process control
provides a slug at the final stage prior to forming with a consistent
liquid/solid fraction and
predictable viscosity. This state is ideal
to fill the die cavity with a non-turbulent material front, eliminating
entrapped air and preventing part porosity as in the test plates above.
The viscous slug retains its shape until shear force from the hydraulic
press is applied. The real-time controlled, closed-loop press follows
an optimum SSM pressure/velocity curve during the forming cycle, yielding
complex near net shape parts. 
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