Steel 34ХМА (34ХМ)

Designation

Name The value
Designation GOST Cyrillic 34ХМА
Designation GOST Latin 34XMA
Transliteration 34HMA
By chemical elements 34CrMo
Name The value
Designation GOST Cyrillic 34ХМ
Designation GOST Latin 34XM
Transliteration 34HM
By chemical elements 34CrMo

Description

34ХМА steel is used: for the manufacture of forgings of shafts of compressors and gas turbines; blank discs of steam turbines with a working temperature up to 350 °C; billet shafts and solid-forged rotors of stationary and transport steam turbines.

Standards

Name Code Standards
Processing of metals by pressure. Forgings В03 TU 108-1028-81, TU 108-1029-81, TU НЗЛ 342-89
Blanks. Of the workpiece. Slabs В31 TU НЗЛ 341-93

Chemical composition

Standard C S P Mn Cr Si Ni Fe Cu Mo
TU 108-1028-81 0.3-0.4 ≤0.022 ≤0.025 0.4-0.7 0.9-1.3 ≤0.37 ≤0.5 Rest ≤0.25 0.2-0.3
TU 108-1029-81 0.3-0.38 ≤0.022 ≤0.025 0.4-0.7 0.9-1.3 ≤0.37 ≤0.5 Rest ≤0.25 0.4-0.55
TU НЗЛ 342-89 0.3-0.4 ≤0.025 ≤0.025 0.4-0.7 0.9-1.3 0.17-0.37 ≤0.5 Rest ≤0.3 0.2-0.3
Fe is the basis.
According to TU NZL 342-89 the chemical composition is given for steel grade 34XMA.
According to TU 108-1028-81 and TU 108-1029-81 the chemical composition is given for steel grade 34XMA. In the workpieces, deviations in the content of the elements indicated in the table are allowed: carbon ± 0.010%, silicon + 0.030%.
In the manufacture of blanks with discs with hub heights from 450 to 650 mm, the content of phosphorus and sulfur in steel should not be more than 0.018% of each; for metal VDP and ELP, the deviation of manganese content +0.10% / - 0.15% is allowed. In the ESR steel, the sulfur content should not be more than 0.015%. When casting steel without evacuation, for the manufacture of disc blanks with a hub height of more than 300 mm, hydrogen content in the metal must be determined. The results of determination of the hydrogen content are not acceptance-delivery and, at the request of the consumer, are to be entered in the procurement certificate.

Mechanical properties

Section, mm sT|s0,2, MPa σU, MPa d5, % y, % KCU, kJ/m2
Forged billet shafts of compressors and gas turbines, heat-treated in the delivery condition on the other NZL 342-89 (longitudinal samples, in the column of the delivery condition specified strength)
≤650 ≥343 ≥568 ≥17 ≥35 ≥441
≤300 490-687 ≥638 ≥15 ≥35 ≥490
Billet shafts and rotors of steam turbines on the other 108-1029-81 (in the delivery condition specified strength and direction and place the cuttings sample)
- ≥343 ≥569 ≥17 ≥40 ≥390
- ≥324 ≥540 ≥13 ≥32 ≥390
- ≥490 ≥638 ≥15 ≥40 ≥590
- ≥461 ≥608 ≥11 ≥32 ≥450
Forged blanks of disks of steam turbines on the other 108-1028-81 (in the delivery condition specified strength; in cross-section, if regulated, see the recommended height of the hub)
- 392-589 ≥589 ≥17 ≥40 ≥390
- 490-687 ≥657 ≥15 ≥40 ≥490

Description mechanical marks

Name Description
sT|s0,2 Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%
σU Limit short-term strength
d5 Elongation after rupture
y The relative narrowing
KCU Toughness