Special Alloys
Premium Cobalt-Chromium-Molybdenum alloys from PML-engineered for strength, wear resistance, and biocompatibility in critical medical and high-temperature applications.


A high-integrity superalloy engineered to survive the most punishing friction and corrosive environments on Earth, and inside the human body.
Vacuum Induction Melting (VIM) process ensures high-purity CoCrMo ingots with precise alloy control and minimal contamination.
Alloy development begins with customer requirements—tailoring chemistry, trace elements, and melt parameters for target specifications, dimensional requirement
As per customer requirements, mould design carried out and planned for charge preparation, charge sequences in VIM furnace. Careful selection of raw materials are the prime factor to achieve specified chemistry of an alloy.
Virgin elements are charged into the VIM furnace either in air or under vacuum, with precise adjustments made for trace element additions during melting.
The melt is poured under vacuum into precision-engineered molds using an automatic tilting mechanism for defect-free solidification.
Post-casting processes include surface treatment, cropping, and preparation of ingots for downstream processing.
Every batch is tested for chemical composition by Spark- OES / wet analysis / Gas analysis, and physical compliance as per customer specification before secure packaging.
Standards Referenced: ASTM F75, ASTM F1537, SAE AMS 5387
Element | Chemical Composition in wt% | ||
|---|---|---|---|
| Vitallium | ASTM F75 | ASTM F1537 | |
| C | 0.05 Max | 0.35 Max | 0.15 - 0.35 |
| Cr | 26.00 - 30.00 | 27.00 - 30.00 | 26.00 - 30.00 |
| W | - | 0.2 Max | 0.2 Max |
| Si | 1.00 Max | 1.00 Max | 1.00 Max |
| Fe | 0.75 Max | 0.75 Max | 0.75 Max |
| Ni | 1.00 Max | 0.50 Max | 1.00 Max |
| Mn | 1.00 Max | 1.00 Max | 1.00 Max |
| Mo | 5.00- 7.00 | 5.00- 7.00 | 5.00- 7.00 |
| P | Other impurities 0.1 Max | 0.02 Max | 0.02 Max |
| S | 0.01 Max | 0.01 Max | |
| Al | 0.10 Max | 1.00 Max | |
| Ti | 0.10 Max | 0.10 Max | |
| B | 0.01 Max | 0.01 Max | |
| La | - | 0.03 - 0.20 | |
| Co | Balance | Balance | Balance |
ASTM F75 (Cast Alloy)
| Alloy | Mechanical properties* | PML alloy: as cast* | After Heat treatment* |
|---|---|---|---|
| PML ASTM F75 *Typical | Rockwell Hardness (HRC) | 47 HRC | 34 HRC |
| Tensile Strength Ultimate (UTS) | 665MPa Min | 960 MPa | |
| Tensile Strength Yield (YS) | 450MPa Min | 560 MPa | |
| Elongation Break | 8% | 20% | |
| Reduction of Area | - | - |
Ensuring material integrity with 100% PMI testing via our precise XRF analyser.
| Alloy | Mechanical properties* | PML alloy: as cast* | After Heat treatment* |
|---|---|---|---|
| PML ASTM F1537 *Typical | Rockwell Hardness (HRC) | 25 | 25-35 |
| Tensile Strength Ultimate (UTS) | 860MPa | 897MPa Min | |
| Tensile Strength Yield (YS) | - | 517MPa Min | |
| Young’s Modulus (E) | - | - | |
| Elongation Break | - | 20% | |
| Reduction of Area | - | - |
*Typical- Mechanical properties vary according to heat treatment cycle.
Technical Specifications
Engineered to meet demanding specs with consistent quality and adaptable performance.
| Alloy | Mechanical properties* | PML alloy: as cast* | After Heat treatment* |
|---|---|---|---|
| PML Vitallium *Typical | Rockwell Hardness (HRC) | 47 HRC | 34 HRC |
| Tensile Strength Ultimate (UTS) | - | 869 MPa | |
| Tensile Strength Yield (YS) | - | 644 MPa | |
| Young’s Modulus (E) | - | 218 GPa | |
| Elongation Break | Not Applicable | 12% Min | |
| Reduction of Area | Not Applicable | 12% Min |

Engineered for extreme biocompatibility and wear resistance, this high-performance cobalt-chromium-molybdenum alloy provides the exceptional fatigue strength and corrosion defense required for advanced medical implants and aerospace engine components.
Key features
| Input : Batch size | Output | Alloying Elements | Chemistry tolerance | Impurities Max |
|---|---|---|---|---|
| 30 kgs to 600 kgs | Ingot of required shape as per customers requirement | Cr and W on Co- base | +/- 0.5 % for Higher level % (Above 2 digit) and +/- 0.3 % for lower level % (Single digit) | Oxygen < 25ppm Hydrogen < 3ppm Nitrogen < 50ppm All other impurities < 50 ppm |
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Ideal for rapid prototyping, powder manufacturing via VIGA, and precision investment castings, Medical applications Orthopedic Implants (hip, knee, spinal), Dental Prosthetics, Cardiovascular Implants, Aerospace bearings and wear parts, Precision watch components.
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Used in load-bearing orthopedic implants, aerospace, and precision engineering sectors requiring strength, ductility, and corrosion resistance.
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Suitable for dental and orthopedic implants with high fatigue and wear resistance.

With over six decades of expertise, PML delivers high-performance component technologies and precision solutions trusted across critical industries.

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