Nov 16 2012
Topics Covered
IntroductionChemical CompositionPhysical PropertiesMechanical propertiesOther DesignationsFabrication and Heat Treatment Machinability Forming Welding Forging Annealing HardeningApplications
Introduction
Super alloys have good have good creep and oxidation resistance, and include number of elements in different combinations to achieve the desired result. They can be strengthened by performing work hardening, precipitation hardening, and solid-solution hardening. Cobalt-based, nickel-based, and iron-based alloys are three types of super alloys. The cobalt-based super alloys have higher melting points than that of nickel or iron-based alloys. The iron-based super alloys are strengthened by intermetallic compound precipitation in fcc matrix. The nickel-based super alloys consist of solutes such as titanium and/or aluminum with a total concentration of less than 10 atomic %.
Super alloy HPA 60 is the best non-galling stainless steel. The following datasheet gives an overview of super alloy HPA 60.
Chemical Composition
The chemical composition of super alloy HPA 60 is highlighted in the following table.
| Element |
Content (%) |
| Chromium, Cr |
16-18 |
| Nickel, Ni |
8-9 |
| Manganese, Mn |
7-9 |
| Silicon, Si |
3.5-4.5 |
| Carbon, C |
0.1 max |
| Nitrogen, N |
0.08-0.18 |
| Phosphorus, P |
0.04 max |
| Sulfur, S |
0.03 max |
| Iron , Fe |
Remainder |
Physical Properties
The physical properties of super alloy HPA 60 are given in the following table.
| Properties |
Metric |
Imperial |
| Density |
7.7 g/cm³ |
0.28 lb/in³ |
Mechanical properties
The following table outlines the mechanical properties of super alloy HPA 60.
| Properties |
Metric |
Imperial |
| Tensile strength |
724 MPa |
105 ksi |
| Yield strength |
379 MPa |
55 ksi |
| Poisson's ratio |
0.298 |
0.298 |
| Elongation |
35% |
35% |
| Reduction of area |
55% |
55% |
Other Designations
Other designations that are equivalent to super alloy HPA 60 include:
- AMS 5848
- ASTM A193 (B8S, B8SA)
- ASTM A194 (B8S, B8SA)
- ASTM A240
- ASTM A276
- ASTM A479
- ASTM A555
- ASTM A580
Fabrication and Heat Treatment
Machinability
Positive feeds, slow speeds, and resulphurized lubricants are suitable for machining super alloy HPA 60.
Forming
Super alloy HPA 60 can be formed using standard techniques.
Welding
Super alloy HPA 60 can be welded using common welding techniques such as gas metal arc welding, gas tungsten arc welding, and submerged arc
Forging
Super alloy HPA 60 is forged by heating at 1094°C (2000°F) followed by soaking.
Annealing
Super alloy HPA 60 is annealed by soaking at 1038 to 1122°C (1900 to 2050°F) followed by quenching in water or air.
Hardening
Super alloy HPA 60 can be hardened only by cold working.
Applications
Super alloy HPA 60 is used in the following applications:
- Internal combustion valves and seats
- Pump components
- Bridge spacers
- Pin and roller bearings
- High wear applications