This is a martensitic alloy that has been added sulphur thus offering an improved machinability.
Compared to other stainless steel alloy kinds, the machinability characteristics supplied by this particular type of stainless steel are exceptional.
Therefore, this guide will majorly focus on the aspects that make this alloy distinct from other stainless steel alloys. Here, our main concern will be its composition, material properties, machinability and applications.
403 Stainless Steel Composition
The main elements making up this alloy include;
- Carbon
- Silicon
- Sulphur
- Iron
- Manganese
- Chromium
- Phosphorus
403 SS Material Properties
Chemical Properties
The chemical properties of 403 Stainless Steel are illustrated below;
· In this alloy, chromium concentration amounts to 12.3%.
· Sulfur is present in the alloy at a rate of 0.03%.
· Carbon content is 0.15 percent.
· We have the contents of phosphorus at 0.04%.
· Iron makes up a higher amount of alloy components (86%).
· 1.0% of it is manganese.
· 5% of silicon is present.
Physical Properties
The physical property is this alloy is;
· The density of it is 7.80 g/cm3.
Mechanical Properties
The mechanical properties include;
· Its elongation at break is 25% per 50 mm.
· Alloy has a brinell hardness of 139.
· Tensile strength of the material is 485 MPa.
· This alloy’s fatigue strength at 25 mm diameter is 275 MPa.
· Vickers hardness is 153 and the Rockwell hardness is 80.
· The toughness of the knop is 155.
· We have a Poisson’s ratio of 0.27–0.30.
· 310 MPa is the yield strength.
· Shear modulus for this alloy is 76.0 GPa.
· 120 J of izod impact
· The elastic modulus ranges from 190 to 210 GPa.
Physical Properties
The physical property is this alloy is;
· Its density of it is 7.80 g/cm3.
Mechanical Properties
The mechanical properties include;
· Its elongation at break is 25% per 50 mm.
· Alloy has a brinell hardness of 139.
· Tensile strength of the material is 485 MPa.
· This alloy’s fatigue strength at 25 mm diameter is 275 MPa.
· Vickers hardness is 153 and the Rockwell hardness is 80.
· The toughness of the knop is 155.
· We have a Poisson’s ratio of 0.27–0.30.
· 310 MPa is the yield strength.
· Shear modulus for this alloy is 76.0 GPa.
· 120 J of izod impact
· The elastic modulus ranges from 190 to 210 GPa.
Thermal properties
Thermal properties include;
· 21.5 W/Mk is the thermal conductivity.
· At 9.90 m/m°C, its thermal expansion stabilizes.
Fabricating & Machining Stainless Steel Grade 403
Below are the processes that are used during the machining and fabrication of this alloy;
Machinability
This alloy has enhanced shear strength because of the heat treatment’s hardening effect.
Because of this, it requires higher forces during machinability along with low speeds for proper machinability. As a result, the alloy becomes tough, long-lasting machined chips.
Weldability
The parts should be preheated before welding if they are to fit together without having any finish flaws.
The operation is carried out between 180 and 205 0C to avoid cracking, especially for the larger components.
Tempering
This alloy has a form of machinability where specific mechanical qualities are desired. 400°F to 1400°F is the temperature range used for the procedure.
For instance, temperatures between 800°F and 1100° should be reached to achieve great toughness and ductility. The levels of strength and hardness will also decrease as a result of this.
One to two hours should be spent submerging the parts for the tempering process. Larger sections are slightly soaked longer before being cooled by air.
Hardening
This material can be toughened by oil quenching between 1650 and 1800 °F. In order to harden it to various degrees, it can then be cooled from temperatures exceeding 1500 °F.
Annealing
The alloy must be uniformly heated to a temperature between 1500 and 1650°F. Thereafter, it must be cooled by air to 1100°F.
Forging
This alloy can be fabricated using compressive forces like pressing and hammering.
Additionally, the recommended completion temperature for the procedure is above 1400°F, with the process starting at a temperature of 2000°F to 2200°F.
The technique shouldn’t be carried out below 1300 °F to avoid rapturing.
How 403 SS Compare to 304 Stainless Steel
The two alloys compare in the following ways;
| Variable | 403 stainless steel | 304 stainless steel |
| Chemical composition | Due to the high quantities of carbon in this alloy, welding is a little more difficult. | The carbon contents in this alloy are low hence easier weldability is achieved |
| Cost | Because of the higher carbon content and difficulty in production, this alloy is more expensive. | The alloy is less expensive because it has low carbon contents. |
| Resistance to heat | It has lower resistance to heat | The resistance to heat is higher |
| Corrosion resistance | It has low levels of corrosion resistance | This alloy offers excellent corrosion resistance qualities as a result of its greater Chromium content. |
Forms 403 SS Exist
Forms in which this alloy exists in include the following;
- Rods
- Coils
- Plates
- Tubes
- Sheets
- Rolls
403 Stainless Steel Application
Due to its strength and corrosion resistance, this alloy can be used in the following;
- It is employed in the manufacturing of turbine parts and blades in the power generation sector.
- Moreover, it is employed in the production of surgical and dental equipment.
- The production of cutting equipment like knives
Conclusion
With the information in this guide, you can easily decide whether the 403 stainless steel is suitable for you or not.
However, if you have problem choosing the right stainless steel metal, contact Tuolian Metal now.
More Resources:
Stainless Steel Grades – Source: Tuolian Metal
403 Grade Stainless Steel – Source: AZO Material
Stainless Steel Manufacturing – Source: Tuolian Metal
403 vs 304 Stainless Steel – Source: Tuolian Metal
