According to the ASTM B865, the nickel based K500 Monel Alloy Cold Drawn Round Bar is to be Precipitation hardened. This process is carried out by maintaining the Nickel Alloy K500 hollow Bar at an elevated temperature.
Once heated, the Alloy K500 Forged Bar is to be furnace cooled following which the alloy is to be air cooled. A point highlighted by the ASTM B865 specification is that the WERKSTOFF NR. 2.4375 Flat Bar needs to conform to the required mechanical properties in both an aged condition as well as an unaged condition. While the AMS 4676 hot rolled round bar is similar to Alloy 400 in terms of its corrosion resistance, the tensile strength and hardness properties of the ASME SB865 Monel Alloy K500 hex bar are much higher than grade monel 400.
The elevated tensile strength and hardness properties of the Monel K500 Square Bar are attributed to the precipitation hardening process carried out on the alloy. Moreover, adding aluminium and titanium in ASTM B865 UNS N05500 Bright Bar also improves its mechanical properties. In fact, the resultant tensile strength properties of the Nickel Alloy K500 Rod is almost 2 times that of monel 400. A disadvantage of Monel K500 Round Bar in an age-hardened condition is that the alloy is prone to stress corrosion cracking.
| Standard Specifications | ASTM B865 / ASTM SB865 |
| Round bars Dimensions | JIS, AISI, ASTM, DIN, BS, ASME, EN |
| Monel K500 Rod Size |
5 To 500 mm |
| Alloy K500 Round bars Diameter | 0.1 to 100 mm |
| K500 Alloy Bars Length | 100 To 3000 mm Long and Above |
| Round bars Finish | Turned, Polished, Bright, Black, Rough, NO.4 Finish,BA Finish, Matt Finish |
| Bars Tolerance | H13K9, K10, H8, K11, H12, H9, K12, H10, H11 or as per clients’ requirements |
| Form of Nickel Alloy K500 Rod | Square, Billet, Forging, Hex (A/F), Rectangle, Ingot, Round Etc. |
AMS 4676 hot rolled round bar
WERKSTOFF NR. 2.4375 Flat Bars
ASME SB865 Monel Alloy K500 Cold Drawn Round Bar
ASTM B865 UNS N05500 Bright Bars
alloy K500 Round bar
0.500" - 1.750"
| Density | Melting Point | Tensile Strength | Yield Strength (0.2%Offset) | Elongation |
| 8.44 g/cm3 | 1350 °C (2460 °F) | Psi – 1,60,000 , MPa – 1100 | Psi – 1,15000 , MPa – 790 | 20% |
| STANDARD | WNR Material Number | UNS | JIS | GOST | BS | AFNOR | EN |
| K500 | 2.4375 | N05500 |
| Grade | C | Mn | Si | Cu | Fe | Ni | S |
| K500 | 0.25 max | 1.5 max | 0.5 max | 27.00 – 33.00 | 0.5 – 2 | 63.00 min | 0.010 max |
The copper nickel alloy standard specifies a 63% nickel incorporated material that is suitable for high corrosive environments. It is a precipitation hardened grade of material that could be cold worked to further harden the material. Heat treatment is not possible to strengthen the B865 material. So the cold working takes place under room temperatures. This is a slow process and requires sharp tools and experienced professionals to conduct the cold working. The cold worked material has high tensile strength at 1100MPa and high yield strength at 790MPa. The bars are used in marine, chemical and petroleum industries.