Printed from Kezuriba (kezuriba.net/en/materials/skd61/)
SKD61
ISO P (steel)Alloy tool steels (for hot-work dies). Standard: JIS G 4404 (Not confirmed. The JSA preview URLs).
🌐International equivalents
“Close” means composition or properties are not exactly the same. Before substituting, check the values in each standard.
| System | Designation | Number | Relation | Confidence |
|---|---|---|---|---|
| JIS | SKD61 | JIS G 4404 | — | |
| AISI | H13 | UNS T20813 | close | Agrees in 2+ sources[1][2][9][10] |
| EN | X40CrMoV5-1 | 1.2344 | close | Agrees in 2+ sources[1][2][11][7] |
| GB | 4Cr5MoSiV1GB/T 1299 tool and die steels | close | Agrees in 2+ sources[9][11] |
Differences between the equivalents (from the sources)
- AISI H13: Agrees between Daido (DHA1: JIS SKD61, AISI H13 eq.), Proterial (DAC: AISI-H13 / JIS-SKD61), Kyocera's comparison table and Baosteel's die steel page. UNS T20813 was confirmed only at Carpenter (a US steelmaker). The AISI column in Proterial's table has C 0.30–0.40, Mn 0.20–0.40, Mo 1.25–1.75 and V 0.80–1.20, so its ranges differ from JIS
- EN X40CrMoV5-1: Agrees between Daido (WNr. 1.2344 eq.), Proterial and Baosteel. The DIN/W-Nr. column in Proterial's table has Mo 1.20–1.50 and V 0.85–1.15, so its lower limits are higher than JIS (Mo 1.00–1.50, V 0.80–1.15). Dörrenberg describes 1.2344 as "Similar to AISI H13"
- GB 4Cr5MoSiV1: Agrees between Kyocera's comparison table (SKD61 = 4Cr5MoSiV1 = H13) and Baosteel's die steel page (4Cr5MoSiV1: US approximate H13, Japanese approximate SKD61, European approximate 1.2344). Kyocera matches SKD6 with 4Cr5MoSiV (a grade without the trailing "1"), so the corresponding grade changes depending on whether the trailing "1" is present. The grade name in GB/T 1299-2025 was not confirmed
📄Related specifications (AMS, ASTM etc.)
Specifications called up on purchase orders and drawings. AMS are SAE aerospace material specifications, split by product form (bar, plate, forging), melting practice and heat treatment. Standard texts are paid, so only titles and scopes checked on the publishers’ public pages are shown.
| Spec | Scope | Confidence |
|---|---|---|
| ASTM A681 | Standard Specification for Tool Steels AlloyComposition, hardness, etc. of alloy tool steels (bars, plates, wire, forgings, etc.). The current edition is A681-24. The public ASTM page does not state that H13 is included, so whether this designation is covered was not confirmed | One source / reference[12] |
All ASTM standards on Kezuriba: ASTM standards quick reference.
⚗Chemical composition (mass %)
As specified in JIS G 4404 (Daido DHA1 chemical composition table [equivalent standard JIS SKD61], JIS column of the Proterial DAC page)
⚖Density
—
Not confirmed
No density is given in Japanese manufacturers' materials (Daido DHA1 physical properties table, Proterial). No density was found in the EN 1.2344 datasheets (Dörrenberg, thyssenkrupp) either. The Uddeholm and Eschmann materials could not be accessed and were not checked
The density could not be confirmed. In the weight calculator, use “Steel, general value” or enter your own.
💪Mechanical properties
“Reference” values are not specified minimums from the standard but figures published by makers and others.
| Condition | Tensile MPa | Yield MPa | Elong. % | Hardness | Type of value |
|---|---|---|---|---|---|
| Annealed (820–870℃, slow cooling) | — | — | — | HBW 229 max | Manufacturer standard value (annealed hardness of Daido DHA1, delivery hardness of Proterial DAC). Dörrenberg's EN 1.2344 also has a maximum of 229 HB annealed Agrees in 2+ sources[1][2][7] |
| Quenched 1020℃ air cooled (oil cooled) + tempered 550℃ air cooled | — | — | — | HRC 50 min | Standard heat-treatment hardness in the manufacturer's materials (Proterial DAC) One source / reference[2] |
| Quenched 1000–1050℃ air cooled + tempered 550–650℃ air cooled | — | — | — | HRC 53 max (Daido DHA1) / HRC 40–52 (Sanyo QD61, tempered 550–650℃ ×2) | Values in the manufacturers' materials (written differently for each brand). Not JIS specified values One source / reference[1][8] |
1 MPa ≈ 145 psi (0.145 ksi). Hardness conversion · unit converter
🔧Machinability notes (as stated in the sources)
- Sandvik Coromant states that for high-alloy steels, machinability decreases as alloy content and hardness increase. After quenching and tempering (over 45 HRC) it is treated as ISO H, and the conditions differ greatly from annealed material (≤229 HBW)[3]
- Daido states that DHA1 has "excellent hardenability" and "excellent temper softening resistance at high temperatures"; working hardness by application is 41–48 HRC for Al and Zn die casting dies and 42–50 HRC for hot press dies, among others. Tool selection changes depending on the hardness at which finishing is done[1]
📚Sources
Primary sources (public documents from makers, industry associations and standards bodies), numbered where each value is cited. Many are in Japanese.
- daido.co.jp https://www.daido.co.jp/common/pdf/pages/products/tool/dha1.pdf
- proterial.com https://www.proterial.com/e/yss/search/dac.html
- sandvik.coromant.com https://www.sandvik.coromant.com/en-us/knowledge/materials/workpiece-materials
- kyocera.co.jp https://www.kyocera.co.jp/prdct/tool/wp-content/uploads/2014/07/2024-2026_A.pdf
- sumitool.com https://www.sumitool.com/downloads/cutting-tools/general-catalog/assets/pdf/a.pdf
- mmc-carbide.com https://www.mmc-carbide.com/permanent/courses/78/group-h.html
- doerrenberg.de https://doerrenberg.de/fileadmin/special_steel/files/pdf_en_products_neues_Design/1.2344_e…
- sanyo-steel.co.jp https://www.sanyo-steel.co.jp/english/product/special_steel/images/pdf/tool_steel_201712.p…
- kyocera.co.jp https://www.kyocera.co.jp/prdct/tool/wp-content/uploads/2016/06/R_2016.pdf
- carpentertechnology.com https://www.carpentertechnology.com/alloy-finder/H13
- esales.baosteel.com http://esales.baosteel.com/baosteel_bsi/sso_teg/cp_pages_tggmjg.jsp
- store.astm.org https://store.astm.org/a0681-08r22.html