UNS S13800 | DIN 1.4534 | ASME SA693 | ASTM A 564 | AMS 5629 | DMS 2100 | HMS 6 1105
Introduction
13-8 stainless is a martensitic precipitation hardening stainless steel that has excellent strength, high hardness, superior toughness and good corrosion resistance. Good transverse toughness properties are achieved by tight chemical composition control, low carbon content, and vacuum melting. Typical applications are large airframe structural components and injection molding equipment.
Stainless steels are known as high-alloy steels. These steels contain good corrosion resistance in comparison with other steels because they contain larger amounts of chromium.
Stainless steels are available in three different groups based on their crystalline structure. These groups include martensitic, austenitic and ferritic. The combination of martensitic and ferritic steels forms a fourth group of stainless steels known as precipitation-hardened steels.
Stainless steel-grade 13-8 is an age hardenable, precipitation stainless steel. This steel has good resistance to stress and general corrosion cracking, high transverse toughness and high strength obtained by a single low temperature heat treatment.
Chemistry
| Ni | Cr | Mo | C | P | S | Si | Mn | N | Al | Fe | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| MIN | 7.5 | 12.25 | 2.0 | – | – | – | – | – | – | 0.90 | – |
| MAX | 8.5 | 13.25 | 2.5 | 0.05 | 0.01 | 0.008 | 0.1 | 0.2 | 0.1 | 1.35 | Balance |
Chemical Composition
The chemical composition of stainless steel-grade 13-8 is outlined in the following table.
| Element | Content (%) |
|---|---|
| Iron, Fe | 76 |
| Chromium, Cr | 12.25-13.25 |
| Nickel, Ni | 7.50-8.50 |
| Molybdenum, Mo | 2.0-2.50 |
| Aluminum, Al | 0.90-1.35 |
| Manganese, Mn | 0.10 |
| Silicon, Si | 0.10 |
| Carbon, C | 0.050 |
| Nitrogen, N | 0.010 |
| Phosphorous, P | 0.010 |
| Sulfur, S | 0.0080 |
Inventory
- 13-8 PH Round Bar
Common Trade Names
- 13-8 Stainless
Features
- Martensitic, precipitation hardening (maraging) stainless steel.
Applications
- Aerospace components
- Injection molding equipment
- Components in the petrochemical and nuclear industries
Physical Properties
Density: 0.279 lb/inch3
Melting Range: 2560 – 2680°F
Electrical Resistivity: 613 Ohm-circ mil/ft
| Temperature, °F | 70 | 212 | 392 | 572 |
| Coefficient of Thermal Expansion, in/in°F x 10-6 | – | 7.2 | 7.5 | 7.8 |
| Thermal Conductivity Btu • ft/ft2 • hr • °F |
8.6 | 9.2 | 9.8 | 10.4 |
| Modulus of Elasticity, psi X 106 |
29.0 | 28.1 | 27.0 | 26.1 |
70°F to indicated temperature
Mechanical Properties
Strength varies with heat treatment condition. The following table shows minimum mechanical properties for the various aged conditions, per AMS 5864.
| H950 | H1000 | H1025 | H1050 | H1100 | H1150 | |
| 0.2 Offset Yield Strength, ksi | 205 | 190 | 175 | 165 | 135 | 90 |
| Ultimate Tensile Strength, ksi | 220 | 205 | 185 | 175 | 150 | 135 |
| Elongation in 2″, % | 10 | 10 | 11 | 12 | 14 | 14 |
| Reduction of Area, % (Longitudinal) | 45 | 50 | 50 | 50 | 50 | 50 |
| Reduction of Area, % (Transverse) | 45 | 50 | 50 | 50 | 50 | 50 |
| Reduction of Area, % (Short-Transverse) | 35 | 40 | 45 | 45 | 50 | 50 |
| Min Hardness, Rockwell | 45 | 43 | – | 40 | 34 | 30 |
Heat Treament
13-8 Stainless is available in the annealed condition, which is also called the solution heat treat condition or Condition A. Solution treat from 1675 – 1725°F for 15 to 30 minutes at temperature. Air cool or oil quench to below 60°F to effect complete transformation to martensite. Aging is normally carried out from 950 – 1150°F, depending on the desired final properties. Heat treatment is usually performed in air. Heat treatment of brazed components may be done in inert atmospheres. Reducing atmospheres should not be used because of the potential for nitrogen contamination.
| Condition | H950 | H1000 | H1025 | H1050 | H1100 | H1150 |
| Temperature, °F | 950±10 | 1000±10 | 1025±10 | 1050±10 | 1100±10 | 1150±10 |
| Time, hours | 4±0.25 | 4±0.25 | 4±0.25 | 4±0.25 | 4±0.25 | 4±0.25 |
Specifications
AMS 5629
DIN 1.4534
ASTM A 564
EN 1.4548
AISI 632
UNS S13800
W. Nr./EN 1.4548
Werkstoff 1.4548
FountainHead Alloys is ISO 9001:2015 approved. © FountainHead Alloys 1996
