When you can start with 316L (stainless steel)
When corrosion and fluid contact are the priority, 316L is a starting candidate. Media chemistry, chlorides, temperature and surface treatment can change the outcome; a general “stainless” statement is not sufficient for every environment.
Evaluating 17-4PH (precipitation-hardening stainless steel)
If strength and corrosion resistance are needed together, 17-4PH can be examined. Powder chemistry, build orientation and heat treatment condition must be the same in any comparison. The CNPC catalogue shows XY and Z mechanical results separately.
Evaluating 18Ni300 (maraging steel)
18Ni300 is a candidate for mould inserts and high-strength parts. Check how target hardness and toughness change with ageing. Do not consider this alloy equivalent to stainless steel in corrosion behaviour.
Build the decision table around the part
Add the corrosion environment, target hardness, required toughness and heat treatment capabilities to the quote file. Compare specimen results under the same test conditions.
Source: CNPC POWDER Company Catalog, printed pp. 3–4, 14–23; powder properties and product comparisons. Catalogue data is a reference for material selection; the datasheet, certificate of analysis of the delivered batch and application tests prevail.