Standard map
Common cross-references
- GB route
- 40Cr; name the governing standard and edition
- ISO / EN route
- 41Cr4; compare the ordered chemistry, condition, and properties
- JIS route
- SCr440; compare the ordered chemistry, condition, and properties
CHROMIUM ALLOY STEEL
40Cr
Round bar for shafts & gears
Annealed or QT bar, with downstream cutting and machining for your next operation.
- DIAMETER
- 20–300 mm
- LENGTH
- 3–12 m
- CONDITION
- Annealed / QT
Published round-bar sizes and delivery conditions.
Supply formsAnnealed or QT round bars · Cut blanks · Machined blanks
Technical specifications & documents
Grade specifications
Cross-references help compare grades; they do not establish interchangeability. The drawing standard, delivery condition, dimensions and inspection scope define the order.
Supply window
Published specification
- Diameter
- 20 - 300 mm
- Length
- 3 - 12 m
- Condition
- Annealed / QT
Property reference
Mechanical property requirements
- Required properties
- State the standard, delivery condition, diameter, and required property target
- Test basis
- State the test position, sampling plan, and required result document
Chemistry reference
- Composition basis
- Use the chemistry table in the standard named on the order
- Substitution check
- Compare the full tables before approving 41Cr4 or SCr440
Application & inspection scope
- Transmission shafts
- Gear components
- Mechanical parts
- Automotive components
- Chemical check
- Mechanical testing
- Ultrasonic testing available
- Dimensional inspection
Buyer questions
Is 40Cr the same as 41Cr4 or SCr440?
40Cr, 41Cr4, and SCr440 are commonly reviewed as cross-reference grade names, but the required project standard should be stated first. Chemical, mechanical, delivery condition, and inspection details still need order-specific review.
Should 40Cr be ordered annealed, normalized, or QT?
Choose the delivery condition to suit the part requirements and the machining and heat treatment that follow. Buyers should state whether they need annealed, normalized, QT, hot rolled, forged, or machined supply, plus any hardness or mechanical-property target.
What inspection points matter for 40Cr round bar?
Common inspection points include chemical composition, mechanical testing when specified, hardness target if required, dimensions, surface condition, MTC, traceability, and third-party inspection when the project requires it.
Documents, tools & technical reading
Condition selection guideProcessing capabilities40Cr lot inspection exampleTension barsFlat barsOpen matched process route40Cr vs 42CrMoCompare a balanced structural grade with a higher-load Cr-Mo option.40Cr vs CK45 shaft materialCompare alloy structural steel and medium carbon steel shaft routes.Quality scope & MTC examplesFactory evidence registerExamples show a format; order documents must match your supply.
Source · 40Cr
40Cr test specimen observed with an ICX41M inverted metallographic microscope. Chai et al. (2022), Figure 1(c); original 20 µm scale retained.
Specimen and condition. The paper identifies lamellar pearlite and ferrite in the 40Cr test material. Its heat-treatment schedule is not reported; this is not labelled as a JOTAIN annealed or QT specimen.
Image treatment. Only the right-hand 40Cr panel is selected from the unaltered source image. The selected panel is fitted uniformly in the hero, with a maximum display width of 640 pixels. A source-coordinate clip excludes all other panels. The original scale is retained; no pixel retouching, sharpening or generated detail.
Jinrong Chai, Guohua Li — Comparative Experiment of Abrasion-Corrosion-Sliding Wear Performance of Two Kinds of Low Alloy Wear-Resistant Steel, 2022. Figure 1(c). DOI and paper · CC BY 4.0.
External research specimen; not a JOTAIN batch image, product acceptance result or promised microstructure. Supplied material is defined by the ordered standard, condition and inspection records.
View the complete source figure
Send your specification
40Cr · include the supplied form, standard, size, condition, quantity and destination.
Discuss your project
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