Three Sisters Forge
Forum Owner-Moderator
Good Morning,
This information comes out of a shop visit. A guy stopped by to order a folder. He felt it was important to share this info.
Metals: I specialized in Implants and reconstruction, faculty at two dental / medical schools (Dr. Jim). Did research on implant materials back in the early 80s. We looked at 440C, ATS-34, CMP metals, 60SV, 30SV, VG-10, and Ti. These were used for implants, blades and drills. Their use in knives is interesting, because these have been used in surgery for years. We found that once these metals went through a "Manufacturing Process" there was little performance difference. Most of the claims were based on one off, very critical handling. Once they made them in big batches, all hell broke loose. The biggest problem is with "sintering" on the surface. Sintering happens when different metals are ground or polished on the same grinders, belts etc. Even batch heat treating will do this.
I took 6 blades from BIG name makers and did EDEX surface scans. ALL were contaminated and sintered on the surfaces. We then did glow discharge to look at the grain at surface levels. The blades were hard, but the grain at electron micro levels was a mess. Picture 440C with bits of ATS-34 pounded in the surface.
Titanium: Most are alloys with Aluminum & Oxygen. Once fit and machined the SURFACE could be significantly altered by bead blasting and anodized, followed by heat. This was the exact process we used for implants. The silica blasting removes contamination and increases surface area for oxidation. The anodizing, if heat stabilized makes the surface very tough.
My recommendations:
Ti: Treat as described above.
Blades:
-Do NOT mix metals on grinding or polishing. Keep separate wheels for polishing.
-Surface clean, bead blast, rinse in distilled water. We use ultra sonics, blades in plastic bags, distilled water.
-Heat treat in small batches.
PS: Nothing cuts like 1095/Cable. Stainless is designed to RESIST corrosion, not cut better.
This information comes out of a shop visit. A guy stopped by to order a folder. He felt it was important to share this info.
Metals: I specialized in Implants and reconstruction, faculty at two dental / medical schools (Dr. Jim). Did research on implant materials back in the early 80s. We looked at 440C, ATS-34, CMP metals, 60SV, 30SV, VG-10, and Ti. These were used for implants, blades and drills. Their use in knives is interesting, because these have been used in surgery for years. We found that once these metals went through a "Manufacturing Process" there was little performance difference. Most of the claims were based on one off, very critical handling. Once they made them in big batches, all hell broke loose. The biggest problem is with "sintering" on the surface. Sintering happens when different metals are ground or polished on the same grinders, belts etc. Even batch heat treating will do this.
I took 6 blades from BIG name makers and did EDEX surface scans. ALL were contaminated and sintered on the surfaces. We then did glow discharge to look at the grain at surface levels. The blades were hard, but the grain at electron micro levels was a mess. Picture 440C with bits of ATS-34 pounded in the surface.
Titanium: Most are alloys with Aluminum & Oxygen. Once fit and machined the SURFACE could be significantly altered by bead blasting and anodized, followed by heat. This was the exact process we used for implants. The silica blasting removes contamination and increases surface area for oxidation. The anodizing, if heat stabilized makes the surface very tough.
My recommendations:
Ti: Treat as described above.
Blades:
-Do NOT mix metals on grinding or polishing. Keep separate wheels for polishing.
-Surface clean, bead blast, rinse in distilled water. We use ultra sonics, blades in plastic bags, distilled water.
-Heat treat in small batches.
PS: Nothing cuts like 1095/Cable. Stainless is designed to RESIST corrosion, not cut better.