What is Chrome steel 1.4021 QT800?
AISI 420 stainless steel, also known as 1.4021, BS 420S37, and X20Cr13, is a martensitic chromium steel. Due to its high chromium content, this material exhibits good corrosion resistance (PREN value 12.0-14.0). After heat treatment, its tensile strength reaches at least 800 MPa. "+QT800" indicates that the steel has undergone quenching and tempering, resulting in a combination of high strength, moderate hardness, and good toughness. This steel is not typically used for cold heading. It is commonly used in the manufacture of cutting tools, such as knives, or for decorative purposes in architecture and design.
Chemical Composition of 1.4021 (X20Cr13), %
| Element | Content (%) |
|---|---|
| C | 0.16 – 0.25 |
| Cr | 12.0 – 14.0 |
| Mn | ≤ 1.50 |
| Si | ≤ 1.00 |
| P | ≤ 0.040 |
| S | ≤ 0.030 |
| Ni | ≤ 0.75 |
| Fe | Balance |
Mechanical Properties of 1.4021 +QT800
| Property | Typical Value |
|---|---|
| Condition | Quenched and Tempered (+QT800) |
| Tensile Strength Rm (MPa) | 750 – 950 |
| Yield Strength Rp0.2 (MPa) | ≥ 600 |
| Hardness (HB) | 220 – 270 |
| Hardness (HRC) | ~ 25 – 32 |
| Elongation A5 (%) | ≥ 12 |
| Impact Toughness KV (J) | ≥ 20 |
| Density (g/cm³) | 7.7 |
| Modulus of Elasticity (GPa) | ~ 200 |
What material is 1.4021 QT800's hardness?
The hardness of 1.4021 QT800 stainless steel is typically around 52 HRC (Rockwell C scale) after proper quenching and tempering, though it can be slightly higher. The "QT800" designation indicates that it is quenched and tempered to a minimum tensile strength of 800 MPa, achieved through a heat treatment process.
What is the difference between 1.4021 +QT800 and 1.4021 +QT700?
The difference between 1.4021 +QT800 and 1.4021 +QT700 is the minimum tensile strength, with QT800 indicating a higher minimum tensile strength than QT700, although both are EN 1.4021 stainless steel in the quenched and tempered condition. The number following "+QT" designates the minimum yield strength in MPa after quenching and tempering, so QT800 signifies a higher minimum yield strength than QT700.
What is the difference between 1.4021+QT800 and 1.4028+QT850 stainless steel?
The main difference lies in the carbon content: 1.4028+QT850 has higher strength and hardness, while 1.4021+QT800 offers better corrosion resistance. Both are martensitic stainless steels, but the higher carbon content of 1.4028 (>0.26%) makes it more suitable for applications requiring extremely high wear resistance and hardness, such as tools and springs.
In addition to 1.4021 stainless steel, GNEE has a large inventory of popular products for your selection. 1.4301, 1.4307, 1.4401, 1.4404, and 1.4541 can be processed into various practical product forms, including plates, coils, pipes, bars, and wires. If you are interested in 1.4408 stainless steel or other products, please feel free to email us. We are happy to assist you.
