Description
Overview of 420
420 stainless steel is a martensitic stainless steel known for its high hardness, wear resistance, and moderate corrosion resistance. When processed into powder, it is widely used in additive manufacturing and metal injection molding (MIM) to create precision components requiring durability and edge retention.
Powder Chemical Composition(wt,-%)
| Element | C | Cr | Ni | Cu | Nb | Mo |
| 420 | 0.35-0.45 | 12.00-
14.00 |
≤0.6 |
– |
≤0.20 | ≤0.20 |
| Element | Si | Mn | S | P | O | Fe |
| 420 | ≤1.00 | ≤1.00 | <0.03 | <0.04 | ≤0.03 | Bal |
Physical Properties
|
Grade |
Size |
Particle size distribution | Hall flow
rate |
Bulk
density |
Tap
density |
||
| D10(μm) | D50(μm) | D90(μm) | |||||
| 420 | 15-53μm | ≥15 | 30-40 | ≤60 | ≤25s/50g | ≥4.0g/cm³ | ≥4.4g/cm³ |
Mechanical Properties
| Grade | Hardness
(HRC) |
Tensile strength
(Ob/Mpa) |
Yield strength
(Opo.2/Mpa) |
Elongation at break(δ5/%) |
| 420 | 48-52 | ≥1950 | ≥1530 | ≥7 |
Heat Treatment Recommendation
| Grade | Recommended HT solution |
| 420 | 1050℃/0.5H/WQ |
Advantages
● High Hardness: Achieves exceptional hardness via heat treatment (quenching & tempering).
● Machinability: Easily polished or ground to fine finishes.
● Cost-Effective: Lower nickel content compared to austenitic steels (e.g., 304/316).
● Wear Resistance: Suitable for abrasive environments.
Limitations
● Moderate corrosion resistance (less than 316L); prone to rust in harsh/marine environments without passivation.
● Requires post-processing (heat treatment) to maximize properties.
Primary Applications
Cutting Tools & Blades
● Ideal for knives, surgical scalpels, and industrial cutting tools due to its ability to achieve high hardness (up to 50-55 HRC) after heat treatment.
Medical Instruments
● Used for reusable surgical tools (e.g., forceps, scissors) that require sterilization and wear resistance.
Mold & Tooling
● Fabricates molds, dies, and wear-resistant parts for plastic injection or stamping industries.
Aerospace & Defense
● Components like bushings, fasteners, and firearm parts benefit from its strength-to-weight ratio.
3D Printing (LPBF/DED)
● Forms complex geometries for automotive or industrial parts needing hardness and moderate corrosion resistance.
Consumer Goods
● Used in cutlery, razors, and decorative items requiring polishability and sharp edges.
