UNS S43100 AISI 431 Martensitic Stainless Steel Bars and Plates
It is a martensitic-ferritic duplex stainless steel. Through rational chemical composition design and heat treatment processes, it combines high strength, good plasticity and toughness, and superior corrosion resistance compared to conventional martensitic stainless steels, while achieving high mechanical properties after heat treatment. In terms of corrosion resistance, it outperforms 12Cr13 (1Cr13) and 10Cr17 (1Cr17), especially in weakly acidic and neutral media. However, its resistance to chloride stress corrosion cracking (SCC) remains inferior to that of 304 austenitic stainless steel. Additionally, it exhibits good toughness, which is better than that of pure martensitic stainless steels (such as 4Cr13), making it suitable for impact-loaded components. It should be noted that the presence of ferrite reduces the toughness of the weld heat-affected zone (HAZ), so strict control of interpass temperature is required during welding. In summary, with its excellent strength-toughness combination and good corrosion resistance, 1Cr17Ni2 occupies an important position in the field of engineering materials. Although its corrosion resistance is not as good as that of austenitic stainless steels, it offers a significant advantage in balancing cost and performance, making it particularly suitable for working environments demanding high strength and toughness.
Applications of UNS S43100
This steel features high mechanical strength and acid resistance for machinery, chemical and energy components, and avoids high-chloride corrosive environments.
- Mechanical manufacturing: It is used to manufacture parts such as shafts, piston rods, pumps, valves, springs and fasteners with strong toughness and corrosion resistance.
- Chemical industry: It is used to manufacture chemical equipment, chemical pipelines, valves, pumps and other equipment in corrosive environments.
- Petroleum industry: It can be used to manufacture equipment and components related to oil exploration and transportation process, such as oil well pipes and sucker rods, which can maintain good performance in harsh petroleum environments.
- Aerospace: Because of its high strength and good corrosion resistance, it can be used to manufacture aircraft components such as fasteners, connectors and shafts, etc.
- Marine engineering: It is applicable to structural components in marine environments, such as ship parts, structural components of offshore platforms, etc., which can resist the corrosion of seawater.
Equivalent Grades and Commonly Used Specifications of UNS S43100
| Steel Grade | Specification | Specification Name |
| 1Cr17Ni2 /
14Cr17Ni2 / S43110 |
GB/T 1220 | Stainless steel bars |
| GB/T 1221 | Heat-resistant steel bars | |
| GB/T 4356 | Stainless steel wire rods | |
| GJB 2294A | Specification for stainless and heat-resisting steel bars for aviation | |
| UNS S43100 | AMS5628 | AEROSPACE MATERIAL SPECIFICATION |
| AMS-S-18732 | Steel Bars, Wire, Forging Stock, Forgings, Tubing (431), Special Quality | |
| MIL-S-18732 | STEEL BARS, WIRE, FORGING STOCK, FORGINGS TUBING (431), SPECIAL QUALITY | |
| QQ-S-763 | STEEL BARS, WIRE, SHAPES, AND FORGINGS; CORROSION RESISTANT | |
| ASTM A276 / ASME SA276 | Standard Specification for Stainless Steel Bars and Shapes | |
| ASTM A314 / ASME SA314 | Standard Specification for Stainless Steel Billets and Bars for Forging | |
| ASTM A580 / ASME SA580 | Standard Specification for Stainless Steel Wire | |
| DMS-1565 | Stainless Steel Bars, Wire, Forging Stock and Forgings, Type 431, Aircraft Quality | |
| 14X17H2 | GOST 5632 | High-alloy steels and corrosion-proof, heat-resisting and high-temperature alloys grades |
Typical Chemical Composition of UNS S43100
|
Elements |
C | Si | Mn | P | S | Ni | Cr |
| Contents% | 0.11~0.17 | ≤0.80 | ≤0.80 | ≤0.040 | ≤0.030 | 1.50~2.50 |
16.00~18.00 |
| Products produced as per other specifications or technical agreements (if need) are available. | |||||||
Typical Heat Treatment Condition and Mechanical Properties of UNS S43100
|
Delivery Condition |
Mechanical Properties of Heat-Treated Specimens | ||||||
| Rp0.2/(N/mm2) | Rm/(N/mm2) | A/% | Zb/% | Aku2d/J | HBW |
HRC |
|
|
Annealed Condition（680℃-700℃ high temperature tempering, air） |
/ | / | / | / | / | ≤285 | / |
| Q+T（950℃-1050℃, oil; 275℃-350℃, air） | / | ≥1080 | ≥10 | / | ≥39 | / |
/ |
| Products produced as per other specifications or technical agreements (if need) are available. | |||||||
Process Properties
Hot working: This kind of steel has poor thermal conductivity and should be heated slowly below 850℃. The appropriate hot working temperature is 1130~1180℃,the final processing temperature should be greater than 850℃, and slow cooling or timely annealing is required after hot working.
Cold working: This kind of steel has a high degree of cold hardening and a high sensitivity to cold working microcracks.The deformation during cold drawing should be controlled at 11%~18%, and annealing should be done within8h after cold drawing.
High Temperature Mechanical Properties of UNS S43100 Oil-Cooled at 1030℃ and Tempered at 680℃
|
Test temperature T(℃) |
Tensile strength
σb(MPa) |
Yield strength
σ0.2(MPa) |
Elongation
δs(%) |
Cross-section shrinkage ratio ψ(%) |
|
20 |
942 | 755 | 17 | 59 |
| 300 | 854 | 686 | 14 |
53 |
|
400 |
785 | 637 | 13 | 57 |
| 500 | 637 | 549 | 18 |
66 |
|
600 |
353 | 353 | 29 |
88 |
Endurance Strength and Creep Strength of UNS S43100 (Oil Quenched and Tempered Samples at 649℃)
|
temperature T(℃) |
σb/1000,MPa | σb/10000,MPa |
σy/10000,MPa |
|
482 |
235.4 | 157 | 137.3 |
|
593 |
73.6 | 49 |
34.3 |
| 649 | 39.2 | 24.5 |
24.5 |
Corrosion Resistance of UNS S43100
|
Medium Conditions |
Corrosion rate /mm/a | Medium Conditions | Corrosion rate /mm/a | ||||
| Media | Concentration
% |
Temperature
℃ |
Media | Concentration
% |
Temperature ℃ |
||
|
Nitric acid |
10 |
50 | <0.1 | Sodium hydroxide | 20 | Boiling | <0.1 |
|
10 |
85 | <0.1 | 30 | 20 |
<0.1 |
||
| 30 | 60 | <0.1 | 30 | 100 |
<1.0 |
||
|
30 |
Boiling | <1.0 | 40 | 90 | <1.0 | ||
| 50 | 50 | <0.1 | 50 | 100 |
<1.0 |
||
|
50 |
80 | 0.1-1.0 | 60 | 90 | <1.0 | ||
| 50 | Boiling | <3.0 | Phosphoric acid | 5 | 20 |
<0.1 |
|
|
60 |
60 | <0.1 | 5 | 85 | <0.1 | ||
| Sulfuric acid | 1 | 20 | 3.0-10.0 | 10 | 20 |
<3.0 |
|
|
5 |
20 | >10.0 | 25 | 20 | 3.0-10.0 | ||
| 10 | 20 | >10.0 | Hydrochloric acid | 1 | 20 |
<3.0 |
|
|
Acetic acid |
10 |
75 | <3.0 | 2 | 20 | 3.0-10.0 | |
| 10 | 90 | 3.0-10.0 | 5 | 20 |
>10.0 |
||
|
15 |
20 | <1.0 | Potassium hydroxide | 25 | Boiling | <0.1 | |
| 15 | 40 | <3.0 | 50 | 20 |
<0.1 |
||
|
25 |
50 | <1.0 | 50 | Boiling | <1.0 | ||
| 25 | 90 | <3.0 | 68 | 120 |
<1.0 |
||
|
25 |
Boiling | 3.0-10.0 | Solution | 300 | >10.0 | ||
| Sodium hydroxide | 10 | 90 | <0.1 | Aluminum sulfate | 10 | 50 |
<0.1 |
|
20 |
50 | <0.1 | 10 | Boiling |
1.0-3.0 |
||
Product Forms and Size Range of UNS S43100
|
Product forms |
Size range |
|
Bars |
Diameter or side length: 5.0mm~1000mm |
| Flats |
thickness: 4.0mm~1000mm width: 300mm~2200mm |
| Produce as other form and size according to technical requirements are available. | |
