FabDigit

High Strength SS · Martensitic

Stainless Steel 420J1

Stainless Steel 420J1 is a high strength stainless steel — cutlery-grade martensitic stainless. Typical values: 345 MPa yield, 7.74 g/cm³, rated to 650 °C. Available for CNC machining at FabDigit.

CNC machiningPremium cost $$$

Properties

Typical room-temperature values in the Annealed condition. Metric first, imperial in gray. The bars show where 420J1 sits against the other 87 stainless steel grades in the catalog.

Datasheet

Yield strength345 MPa50 ksi
Tensile strength720 MPa104 ksi
Hardness95 HRB213 HB
Density7.74 g/cm³0.28 lb/in³
Specific strength (yield ÷ density)45
Min service temp-50 °C-58 °F
Max service temp650 °C1,202 °F
Electrical conductivity2.8 % IACS1.6 MS/m
MachinabilityFair40 / 100
WeldabilityPoor20 / 100
FormabilityFair40 / 100
ISO 513 machining groupM

Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.

Against other stainless steel grades

Yield strength345 MPa 50 ksi
208 MPafamily median 275 MPa760 MPa
Tensile strength720 MPa 104 ksi
483 MPafamily median 620 MPa1,035 MPa
Density7.74 g/cm³ 0.28 lb/in³
7.7 g/cm³family median 7.8 g/cm³8 g/cm³
Hardness (HB equiv.)213 HB
158 HBfamily median 185 HB421 HB
Max service temp650 °C 1,202 °F
480 °Cfamily median 760 °C1,020 °C
Electrical conductivity2.8 % IACS 1.6 MS/m
2.1 % IACSfamily median 2.4 % IACS3 % IACS
Machinability40 / 100
29 / 100family median 40 / 10075 / 100
Relative cost48
34family median 4858

Strength versus weight in the stainless steel family

Yield strength against density for every stainless steel grade FabDigit runs. 420J1 is highlighted; hover a dot for its name, or open the interactive family chart.

2003005007001,0001,5007.67.88Density (g/cm³)Yield strength (MPa) — log scale301303304304L4302205316316LAlloy 20Nitronic 50Nitronic 6013-8 PH15-5 PH17-4 PH17-7 PH309310321330A286410416420420C420V440A440CS30V201202302302HQ303Se304H304LN304Cu305308L309S310S314316LVM316Ti316F316LN317317L321H347347H20Cb-3403405409410S410HT416Se420F420J2422429430F431434436439440B440F4414444461.411615-7 MoCustom 450Custom 465PH 13-8 Mo660210123042507255Zeron 100904L254 SMOAL-6XNCX420J1

Manufacturability

The process limits FabDigit's quote engine applies to 420J1. Design inside these and the part quotes instantly; outside them it routes to an engineer.

CNC machining

MachinabilityFair40 / 100
ISO material groupM.4
Cutting speed (rough / finish)140 / 170 m/min
Minimum wall0.8 mm
Minimum internal radius1.5 mm
Drill depth limit4× diameter
Best surface (machined / polished)Ra 1.6 /
Hardenable after machiningNo

Conditions and tempers

How 420J1 is supplied and what each state is for. The default is what FabDigit quotes unless your drawing says otherwise.

ConditionBest forYield MPaTensile MPaElong. %Hardness
AnnealedDefault
Temper
Softest supply state — for forming, or when you heat-treat after machining
Hardened & Tempered
Heat Treat State
Delivered at final hardness — no heat treat after machining

Heat treatment and post-processing

Operations FabDigit's suppliers routinely run on 420J1, ranked by how often they make sense for this grade.

Heat treatment

Solution AnnealDissolve carbides; reset austenite (stainless)
Stress ReliefReduce residual stress without changing structure
Quench & TemperAchieve target hardness with controlled toughness2855 HRC

Post-processing

Manual DeburrDeburrstandard
Passivate (Citric)Passivation
Edge Break (0.5mm)Deburr
Passivate (Nitric / AMS 2700)Passivation
ElectropolishPolish
Glass Bead BlastBlast
Laser MarkMarking
CMM InspectionInspection
FAI ReportInspection
Individual BagPackaging

Surface finishes for 420J1

Coatings and treatments compatible with stainless steel on the processes 420J1 runs on. Pick them in the quote configurator or call them out on the drawing.

Passivation

  • Electropolishing
  • Passivation (Stainless Steel)
  • Pickling

Plating

  • Chrome Plating
  • Electroless Nickel (EN)
  • Gold Plating
  • Hard Chrome Plating
  • Nickel Plating
  • Silver Plating

PVD Coating

  • AlCrN
  • AlTiN
  • CrN
  • DLC
  • MoS2
  • TiAlN
  • TiB2
  • TiCN
  • TiN
  • WC/C
  • ZrN

Organic Coating

  • Cerakote
  • Epoxy Coating
  • Painting
  • Powder Coating
  • PTFE Coating

CVD Coating

  • CVD Al2O3
  • CVD TiCN
  • CVD TiN
  • Multilayer CVD

Marking / Decoration

  • Chemical Etching
  • Dot Peen Marking
  • Electro-chemical Etching
  • Ink Stamping
  • Laser Marking
  • Mechanical Engraving
  • Steel Stamping
  • Vibro Engraving / Scribing

Black / Phosphate

  • Black Oxide

Thermal Spray

  • HVOF Coating
  • Plasma Spray

Equivalent designations

Standards and trade names that resolve to Stainless Steel 420J1 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.

EN / DIN / Werkstoff-Nr.
1.4021X20Cr13
JIS
SUS420J1

Stock forms

Raw-material forms FabDigit sources 420J1 in.

BarPlate

Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.