
The grade 301 stainless steel has five different temper conditions 1/4 hard, half hard, 3/4 hard, full hard, and spring hard. These temper conditions depend upon the required strength of 301 stainless steel. The 301 stainless steel has excellent corrosion resistance and a bright surface finish; therefore, it is used in many structural and decorative applications.
Due to its high work hardening rate, yield strength and tensile strength will increase significantly with each addition of cold work. The tempering process plays a very important role in making stainless steel.
Tempering is when we heat the stainless steel to a specific, precise temperature below the critical point. This process is done in open air or vacuum. Mostly the different temper conditions of 301 stainless steel are obtained through cold working, not heat treating.
What is 301 half hard stainless steel?
The austenitic stainless steel 301 half hard has undergone cold rolling to achieve its half hard condition. The 301 1/2 hard has minimum 930 Mpa tensile strength and 510 Mpa yield strength, which makes it perfect for many applications.
The different tempers conditions of 301 stainless steel and mechanical qualities are obtained through cold working. Moderate tensile strength is required for the 301 half hard (AMS 5518) material to produce items that need strength and require only moderate drawing or forming.
What is 301 full hard stainless steel?
301 full hard stainless steel is austenitic stainless steel that is cold rolled to a full hard state, making them different from other 301 forms. This makes the metal more suitable for forming and extends its durability. Type 301 has a minimum yield strength of 1030 Mpa and a minimum tensile strength of 1320 Mpa in its full hard condition. It is perfect for springs because of its hardness and toughness combination.
301 half hard AMS 5518 VS 301 full hard AMS 5519
Half hard AISI 301 and full hard AISI 301 are grades of the same material. They both share an alloy composition and many physical characteristics, but due to different processing, they acquire different mechanical properties.
The tensile strength and hardness of 301full hard stainless steel are greater than half hard. Therefore, it is used where high tensile strength and hardness are required. On the other hand, 301 half hard stainless steel has more ductility, formability, and toughness than full-hard stainless steel. The half hard stainless steel is mainly used where we need strength, drawing and forming properties.
Comparison of 301 half hard and 301 full hard
When we compare 301 half hard and full hard, there are some differences in their properties. Let’s see the comparison from the following tables.
Mechanical properties
Mechanical properties | Half Hard AMS5518 | Full Hard AMS 5519 |
Tensile strengthMin MPa | 930 | 1320 |
Yield strength0.2% Min MPa | 510 | 1030 |
Elongation | 10% | 0-3% |
Hardness Vickers | 310-370 HV | 430-490 HV |
Shear strengthMPa | 730 | 860 |
Fatigue strengthMPa | 540 | 550 |
Poisson’s ratio | 0.28 | 0.28 |
Shear modulusGPa | 77 | 77 |
Thermal properties
Thermal properties | Half Hard AMS5518 | Full Hard AMS 5519 |
Latent heat of fusionJ/kg | 280 | 280 |
Maximum temperature corrosion°C | 410 | 410 |
Maximum temperature mechanical°C | 840 | 840 |
Specific heat capacity J/kg-K | 480 | 480 |
Thermal conductivity W/m-k | 16 | 16 |
Thermal Expansion µm/m-K | 17 | 17 |
Physical properties
physical properties | Half Hard AMS5518 | Full Hard AMS 5519 |
Density g/cm3 | 7.88 | 7.88 |
Melting range°C | 1399-1421 | 1399-1421 |
Specific gravity | 8.03 | 8.03 |
Modulus of elasticity in tensionGPa | 193 | 193 |
Common calculations
Properties | Half Hard AMS5518 | Full Hard AMS 5519 |
Pitting Resistance | 18 | 18 |
Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 220 | 99 |
Resilience: Unit (Modulus of Resilience), kJ/m3 | 1880 | 2970 |
Stiffness to Weight: Axial points | 14 | 14 |
Stiffness to Weight: Bending, points | 25 | 25 |
Strength to Weight: Axial, points | 42 | 52 |
Strength to Weight: Bending, points | 32 | 37 |
Thermal Diffusivity, mm2/s | 4.2 | 4.2 |
Thermal Shock Resistance points | 25 | 31 |
Chemical composition
Elements | Half Hard | Full Hard |
Carbon | 0.15% Max | 0.15% Max |
Manganese | 2.0% Max | 2.0% Max |
Silicon | 1.0% Max | 1.0% Max |
Chromium | 16.00-18.00% | 16.00-18.00% |
Nickel | 6.00-8.00% | 6.00-8.00% |
Phosphorus | 0.045% Max | 0.045% Max |
Sulfur | 0.030% Max | 0.030% Max |
Nitrogen | 0.10% Max | 0.10% Max |
Iron | Balance | Balance |
Applications of 301 half hard and 301 full hard stainless steel
Due to its good corrosion resistance, high ductility, and strength, 301 half hard and full hard stainless steel are used in many applications.
Standard applications for stainless steel 301 Half Hard and Full Hard include the aerospace, automotive, architectural, ornamental, industrial, and food and beverage industries.
- Wheel shield
- Kitchen utensils
- A hose clamp
- Roof drainage techniques
- Belt conveyors
- Bodies of trucks and trailers
- Springs
- Automobile trim and molding