Would a pure chromium rod be an effective armor penetrator?

No. Chromium density is just over 7 grams per cubic centimeter. This is extremely “light” compared to other penetrator metals. read more

Long rod perpetrators operate as hydrodynamic materials where its the density of the materials that matter far more then there strengths. The perpetrator only needs to be sufficiently strong to not break on firing or shatter on impact. A pure chromium rod would likely not be strong enough. read more

So, in short, the estoc could not penetrate plate armor in the sense of going through it, but rather in the sense of working around it. Edit: Many of you have been pointing out that an estoc user would not be more agile than a knight. read more

Because pure tungsten is very brittle, the sintering must take place together with nickel and iron. Usual is 93% W, 6% Ni and 1% Fe. Then the density amounts to approximately 17. 5 g/cm^3. read more