420J1 VS. 420J2 Stainless Steel: What’s The Difference?

420J1 VS. 420J2 Stainless Steel: What's the Difference?

Generally speaking, the oxidation resistance of stainless steel strips is slightly lower. 420 belongs to the martensitic stainless steel family. Materials in the martensitic series gain hardness through heat treatment processes such as quenching.

420J1 and 420J2 grades also obtain hardness by heating at high temperatures and then quenching in oil or open air. The carbon concentration mainly determines the maximum quenching hardness. Both 420J1 and 420J2 grades of stainless steel are known for their hardness and corrosion resistance. 420J2 is harder than 420J1, Because of the high carbon concentration in its composition. The recommended quenching temperature is 980-1050°C. Both grades have magnetic properties.

After heat treatment, the hardness of 420 series steel is around HRC52-55, and the damage resistance is average. Because it is easy to cut and polish, it can be used in tool production.

If you would like to learn more about 420J1 and 420J2 stainless steel and their differences, please contact us or download the technical document below!

 

420J1 VS. 420J2 Stainless Steel.pdf

 

What is 420J1 stainless steel?
420J1 has the characteristics of wear resistance, corrosion resistance, high hardness, and the price is lower than stainless steel 420J2.
Grade 420J1 can be hardened by heat treatment (quenching). This ability, combined with their high corrosion resistance, makes them suitable for a wide range of applications.

What is 420J2 stainless steel?
420j2 stainless steel strip
Grade 420J2 stainless steel is affordable and very corrosion-resistant. It resists mild corrosion, domestic, and industrial conditions. It is also resistant to dilute nitric acid.

420J2 stainless steel is manufactured in accordance with the American ASTM standard, the daily standard SUS420J2, and the new national standard 30Cr13.

420J2 ss grade is known for its good strength and reasonable impact resistance after quenching and tempering.

Material properties in various environments
Grade 420 performs well and provides excellent corrosion resistance in all weather conditions. It is also resistant to ammonia, carbonic acid, crude oil, detergent solutions, vinegar, food acids, various petroleum products, and steam. It is quenched and Two forms of tempering make it more suitable for various temperature conditions.

 

Strength and Durability of 420J1 Stainless  vs. 420J2 Stainless Steel

tensile strength
Due to the higher carbon content, the tensile strength of 420J2 is higher than that of 420J1. 420 J2 has better strength and corrosion resistance; therefore, it is mainly used where higher strength and better corrosion resistance are required.

hardness
After quenching, the hardness of 420J2 increases compared to 420J1 stainless steel. Heating 420J2 grade stainless steel to 950–1020°C (1742–1868°F) and holding it there until the temperature is constant throughout the part is one way to harden it.

Yield Strength
Yield strength is the point on the stress-strain diagram where the elastic limit ends and the plastic limit begins. Hard metals generally have higher yield strengths than soft metals. Offset by up to 0.2%, 420J1 has a yield strength of 440 MPa, while 420J2 has 540 MPa.

Chemical composition of 420J1 stainless steel and 420J2 stainless steel

420J1 Stainless Steel vs. 420J2 Stainless Steel – Weldability Differences
melting point
420J1 and 420J2 ss alloys have almost the same melting points due to the same composition, differing only in the carbon content. The melting points of these alloys range between 2642 and 2750 °F and 1450 and 1510 °C.

weight
Since both grades have the same density and are both 420 stainless steel series, 420J1 and 420J2 have the same weight for a given volume.

Corrosion resistance
Both grades of stainless steel exhibit excellent corrosion resistance. 420J2 has a higher carbon content; therefore, it is more susceptible to corrosion than 420J1 in more humid environments and salt water conditions.
Welding Technology
The welding techniques for both alloys are the same as they belong to the same 420 stainless steel series. 420J2 and 420J1 stainless steels are easy to weld. Welding in the annealed, hardened, and tempered condition is not recommended as it can cause brittleness and cold cracking.

cost
The price difference between these stainless steel grades is minimal. 420 J2 is in greater demand than 410J1 due to its slightly higher carbon content and harder texture. Prices also fluctuate with changes in market value.

Weight and density comparison
Density of 420J1 stainless steel
The density of any substance is determined by its mass per unit volume. The density of 420J1 stainless steel is 7.8 (g/cubic centimeter)

Density of 420J2 stainless steel
420J2 and 420J1 belong to the same series of stainless steels; therefore, both alloys have approx. the same density value, such as 7.8 (grams/cubic centimeter).

 

Applications and industries

420 stainless steel
Stainless steel 420J2 is mostly used to make diving knives, ordinary kitchen knives, surgical instruments, hand tools, pump shafts, swords, and daggers.
Stainless  420J1 is most commonly used in food preparation equipment, kitchen knife blades, industrial equipment blades, machine parts, surgical instruments, and decorative applications.