When evaluating metal powder sintering, you must prioritize material density, as it directly correlates with mechanical strength; typically, high-performance parts require a relative density of 90% to 98%. Key materials include Stainless Steel (316L, 17-4PH), Titanium alloys, and Copper. Ensure the supplier specifies dimensional tolerances (standardly ±0.5% or tighter with secondary sizing) and surface roughness (Ra), which usually ranges from 0.8 to 3.2 μm depending on the powder mesh size used.