English 
T: +86-0731-85185770
E: enquiry@qilumetal.com
E: enquiry@qilumetal.com
No. 18 Xiangfu Middle Road,Yuhua District, Changsha City
 |
| Quantity: | |
|---|---|
630
Qilu
AISI 630 (also known as 17-4PH) is a premium precipitation-hardening martensitic stainless steel renowned for its exceptional combination of high strength, superior corrosion resistance, and excellent mechanical properties. You can find its equivalent in different steel standards, such as: X5CrNiCuNb16-4/1.4542 from Europe standard EN 10088-3, 0Cr17Ni4Cu4Nb/05Cr17Ni4Cu4Nb from China standard GB/T 1220, SUS630 from Japan standard JIS G4303, 09X17H7Ю1 from Russia standard GOST 5632-72.
630 stainless steel offers exceptional hardness after heat treatment, good weldability, and resistance to stress corrosion cracking, making it suitable for high-performance applications. Whether you require robust components for aerospace missions, corrosion-resistant parts for oil and gas operations, or precision tools for medical use, AISI 630 stainless steel delivers reliable performance and long-lasting durability.
AISI 630 stainless steel has well-established equivalent grades in major global steel standards, ensuring consistency and compatibility across international projects.
Country | USA | EN | China | Japan | Russia |
Standard | ASTM A693 | EN10088-3 | GB/T1220 | JIS G4303 | GOST 5632-76 |
Grade | 630/17-4PH | X5CrNiCuNb16-4/1.4542 | 05Cr17Ni4Cu4Nb | SUS630 | 09X17H7Ю1 |
The precise chemical composition of AISI 630 and its equivalent grades is critical to achieving their outstanding properties. All values are maximum limits unless specified as a range.
Grade | C | Si | Mn | P | S | Cr | Ni | Cu | Nb |
630 | 0.07Max | 1.0Max | 1.0Max | 0.040Max | 0.030Max | 15.00-17.50 | 3.00-5.00 | 3.00-5.00 | 0.15-0.45 |
X5CrNiCuNb16-4/1.4542 | 0.07Max | 0.7Max | 1.5Max | 0.040Max | 0.030Max | 15.00-17.00 | 3.00-5.00 | 3.00-5.00 | |
05Cr17Ni4Cu4Nb | 0.07Max | 1.0Max | 1.0Max | 0.040Max | 0.030Max | 15.00-17.50 | 3.00-5.00 | 3.00-5.00 | |
SUS630 | 0.07Max | 1.0Max | 1.0Max | 0.040Max | 0.030Max | 15.00-17.50 | 3.00-5.00 | 3.00-5.00 | |
09X17H7Ю1 | 0.09Max | 0.8Max | 0.8Max | 0.035Max | 0.025Max | 16.50-18.00 | 6.50-7.50 | / |
AISI 630 stainless steel’s mechanical performance is optimized through heat treatment, including solution annealing and precipitation hardening. Below are the key mechanical properties for major grades, as specified by their respective standards.
Grade | Heat treatment | Tensile strength | Yield strength | Alongation | Area of reduction | Hardness | |
0Cr17Ni4Cu4Nb | Solution Annealing | / | / | / | / | HBW363 Max | |
Age Hardening | 480℃ | 1310Mpa Min | 1180Mpa Min | 10% Min | 40% Min | HBW375 Min | |
550℃ | 1070Mpa Min | 1000Mpa Min | 12% Min | 45% Min | HBW331 Min | ||
580℃ | 1000Mpa Min | 865Mpa Min | 13% Min | 45% Min | HBW302 Min | ||
620℃ | 930Mpa Min | 725Mpa Min | 16% Min | 50% Min | HBW277 Min | ||
SUS630 | Solution Annealing | / | / | / | / | HBW363 Max | |
H900 | 1310Mpa Min | 1175Mpa Min | 10% Min | 40% Min | HBW375 Min | ||
H1025 | 1070Mpa Min | 1000Mpa Min | 12% Min | 45% Min | HBW331 Min | ||
H1075 | 1000Mpa Min | 860Mpa Min | 13% Min | 45% Min | HBW302 Min | ||
H1150 | 930Mpa Min | 725Mpa Min | 16% Min | 50% Min | HBW277 Min | ||
Steel grade | Thickness | HT condition | Tensile strength | Yield strength | Alongation | Impact value at RT/J | Hardness /HBW | ||
L | Tr | L | Tr | ||||||
X5CrNiCuNb16-4/1.4542 | 100mm Max | AT | 1200Mpa Max | / | / | / | / | / | 360Max |
P800 | 800-950Mpa | 520Mpa Min | 18% Min | / | 75J Min | / | / | ||
P930 | 930-1100Mpa | 720Mpa Min | 16% Min | / | 40J Min | / | / | ||
P960 | 960-1160Mpa | 790Mpa Min | 12% Min | / | / | / | / | ||
P1070 | 1070-1270Mpa | 1000Mpa Min | 10% Min | / | / | / | / | ||
AT=Solution annealed; P= Precipitation hardened
For X5CrNiCuNb16-4 / 1.4542, the minimum 0.2% proof strength at elevated temperatures is as follows:
Steel garde | HT condition | Minimum 0.2% proof strength at a temperature of: | ||||
100℃ | 150℃ | 200℃ | 250℃ | 300℃ | ||
X5CrNiCuNb16-4/1.4542 | Mpa or N/mm2 | |||||
P800 | 500 | 490 | 480 | 470 | 460 | |
P930 | 680 | 660 | 640 | 620 | 600 | |
P960 | 730 | 710 | 690 | 670 | 650 | |
P1070 | 880 | 830 | 800 | 770 | 750 | |
P= Precipitation hardened
We offer AISI 630 stainless steel in a wide range of product types, sizes, and surface finishes to meet your specific application needs. All products adhere to strict tolerance and straightness standards.
Product type | Size range | Length |
Hot rolled bar | Φ10-Φ130mm | 5000-7000mm |
Hot forged bar | Φ140-Φ600mm | 2000-5800mm |
Hot rolled plate/sheet | T:2-60mm; W:310-810mm | 6000-12000mm |
Hot forged plate | T:70-250mm; W:310-810mm | 2000-5800mm |
Hot Forged block | T: 260-500mm; W: 300-1000mm | 2000-5800mm |
Surface Finish | Turned | Milled | Grinding(Best) | Polished(Best) | Peeled(Best) | Black Forged | Black Rolled |
Tolerance | +0/+3mm | +0/+3mm | +0/+0.05mm | +0/+0.05mm | +0/+0.1mm | +0/+5mm | +0/+1mm |
Straighness | 1mm/1000mm max. | 3mm/1000mm max. | |||||
We maintain a large monthly stock of AISI 630 hot rolled bars and forged bars (over 10,000 tons) to ensure quick delivery. Below are common stock diameters:
Hot Rolled Bar Stock Diameters: 10mm, 12mm, 15mm, 18mm, 20mm, 22mm, 25mm, 28mm, 30mm, 32mm, 35mm, 38mm, 40mm, 45mm, 50mm, 55mm, 60mm, 65mm, 70mm, 75mm, 80mm, 85mm, 90mm, 95mm, 100mm, 105mm, 110mm, 120mm, 130mm, 140mm, 150mm, 160mm, 170mm, 180mm, 190mm
Hot Forged Bar Stock Diameters: 200mm, 210mm, 220mm, 230mm, 240mm, 250mm, 260mm, 270mm, 280mm, 290mm, 300mm, 310mm, 320mm, 330mm, 340mm, 350mm, 360mm, 370mm, 380mm, 390mm, 400mm
Stock levels change daily. For real-time availability, please contact our sales team.
All AISI 630 stainless steel products undergo ultrasonic testing in accordance with EN 10228-3 Class III or Sep 1921-84 D/D standards to ensure no internal defects, guaranteeing structural integrity.
We utilize advanced steel making technologies to produce high-purity AISI 630:
EF + LF + VD
EAF + LF + VD
EF + LF + VD + ESR
EAF + LF + VD + ESR
Hot forging temperature: 900℃ - 1150℃
Cooling method: Furnace cooling or air cooling (to prevent cracking and ensure uniform properties)
AISI 630 performance is enhanced through precise heat treatment processes:
Solution Annealing: Heat to 1020℃ - 1060℃, followed by rapid cooling (air or water) to achieve a uniform microstructure.
Precipitation Hardening:
480℃: After solution treatment, heat to 470℃ - 490℃, air cool
550℃: After solution treatment, heat to 540℃ - 560℃, air cool
580℃: After solution treatment, heat to 570℃ - 590℃, air cool
620℃: After solution treatment, heat to 610℃ - 630℃, air cool
High Strength: Achieves exceptional tensile and yield strength through precipitation hardening, outperforming many conventional stainless steels.
Superior Corrosion Resistance: Resists corrosion in mild acids, alkalis, saltwater, and atmospheric environments, suitable for harsh operating conditions.
Good Weldability: Can be welded using standard methods (with proper pre- and post-weld heat treatment to maintain properties).
Stress Corrosion Cracking Resistance: Exhibits excellent resistance to stress corrosion cracking, critical for high-pressure and corrosive environments.
Excellent Machinability: Easy to machine, grind, and form, reducing production time and costs.
Heat Treatable: Customizable mechanical properties via different heat treatment cycles to match specific application requirements.
AISI 630 stainless steel’s unique combination of properties makes it ideal for the following industries and components:
1. Aerospace
Aircraft components: Landing gear parts, engine fasteners, turbine blades, and structural components.
Aerospace equipment: Rocket engine shells, satellite structures, and spacecraft hardware.
2. Oil & Energy Industry
Oil/gas equipment: Valves, pump shafts, downhole tools, and wellhead components.
Nuclear power: Reactor internal fasteners, control rod drive mechanisms, and pressure vessel parts.
3. Chemical & Marine Engineering
Chemical equipment: Acid-resistant pumps, agitator shafts, reaction vessel liners, and piping systems.
Marine environment: Ship shaft systems, propeller shafts, desalination equipment, and offshore platform components.
4. Machinery Manufacturing & Tools
High-stress parts: Gears, bearings, mold inserts, and precision mechanical components.
Medical equipment: Surgical tools, orthopedic implants (e.g., hip and knee replacements), and dental instruments (biocompatible and corrosion-resistant).
AISI 630 is a precipitation-hardening martensitic stainless steel, while 304 is an austenitic stainless steel. Key differences include:
Strength: AISI 630 offers significantly higher tensile/yield strength (up to 1310 Mpa after heat treatment) compared to 304 (around 515 Mpa).
Heat Treatment: AISI 630 can be strengthened via precipitation hardening, while 304 cannot be hardened by heat treatment (only work-hardened).
Corrosion Resistance: 304 has better general corrosion resistance in mild environments, but AISI 630 excels in stress corrosion cracking resistance and performs well in moderate corrosive conditions.
Applications: AISI 630 is used for high-stress, high-performance parts, while 304 is suitable for general-purpose, low-stress applications.
Yes, AISI 630 is weldable using common methods like GTAW (TIG), GMAW (MIG), and SMAW (stick welding). Critical precautions:
Avoid welding in the hardened state; weld in the solution-annealed condition whenever possible.
Use low-heat input to prevent grain growth and maintain mechanical properties.
Post-weld heat treatment (solution annealing + precipitation hardening) is recommended to restore strength and corrosion resistance, especially for critical components.
Use matching filler metals (e.g., ER630 for GTAW/GMAW) to ensure compatibility.
The optimal heat treatment depends on your application:
High Strength: H900 (480℃ aging) – Achieves the highest tensile strength (1310 Mpa min) but lower toughness, ideal for static-loaded components like fasteners.
Balanced Strength & Toughness: H1025 (550℃ aging) or H1075 (580℃ aging) – Offers moderate strength (1000-1070 Mpa min) and improved elongation/impact resistance, suitable for dynamic-loaded parts like gears or shafts.
Maximum Toughness: H1150 (620℃ aging) – Lower strength (930 Mpa min) but highest ductility (16% min elongation), ideal for components requiring shock resistance.
Yes, AISI 630 exhibits excellent corrosion resistance in marine environments, including saltwater and humid coastal atmospheres. It resists pitting, crevice corrosion, and stress corrosion cracking, making it ideal for marine components like ship shafts, propeller parts, and desalination equipment. For extreme marine conditions (e.g., prolonged submersion in highly corrosive water), we recommend periodic maintenance and surface protection (e.g., passivation) to extend service life.
AISI 630 can operate reliably at temperatures up to 315℃ (600°F) for continuous use. At temperatures above 315℃, its mechanical strength (especially yield strength) gradually decreases, and long-term exposure may affect corrosion resistance. For high-temperature applications (315℃+), consult our technical team to evaluate feasibility or explore specialized heat treatment options.
The choice of surface finish depends on your application:
Black Forged/Black Rolled: Cost-effective, suitable for non-critical components or parts that will be further machined.
Turned/Milled: For general-purpose components requiring moderate precision (tolerance +0/+3mm).
Peeled: Improved surface smoothness (tolerance +0/+0.1mm), ideal for shafts or cylindrical parts.
Ground/Polished: Highest precision (tolerance +0/+0.05mm) and smoothness, suitable for critical components like medical implants, precision gears, or high-pressure valves.
Store AISI 630 products in a dry, well-ventilated area to prevent moisture buildup and corrosion. Avoid contact with corrosive substances (e.g., acids, alkalis, or salt) during storage.
Use clean, non-abrasive tools for handling to prevent surface scratches. Scratches can create crevice corrosion sites, so promptly repair minor scratches with a stainless steel polish or passivation treatment.
For long-term storage (6 months+), apply a thin layer of anti-corrosion oil or wrap in moisture-resistant packaging.
Use high-speed steel (HSS) or carbide tools for machining AISI 630. Carbide tools are recommended for higher efficiency and longer tool life.
Maintain a cutting speed of 100-150 m/min (for turning) and 50-100 m/min (for milling) to minimize heat buildup, which can affect material properties.
Use cutting fluids (e.g., mineral oil or water-soluble coolants) to reduce friction and cool the workpiece, improving surface finish and tool life.
Avoid excessive cutting forces, as AISI 630’s high strength can cause tool wear or workpiece deformation.
Passivation: After machining or welding, perform passivation treatment (using nitric acid or citric acid solutions) to enhance corrosion resistance by forming a protective oxide layer on the surface.
Cleaning: Regularly clean AISI 630 components with mild soap and water or a stainless steel cleaner. Avoid abrasive cleaners (e.g., steel wool) that can scratch the surface.
Inspection: Periodically inspect components for signs of corrosion (e.g., pitting, discoloration) or wear. For critical applications, conduct non-destructive testing (e.g., ultrasonic or visual inspection) annually.
After welding, remove weld spatter and slag using a wire brush or grinder.
Perform post-weld heat treatment (solution annealing + precipitation hardening) to restore strength and corrosion resistance.
Inspect welds for defects (e.g., cracks, porosity) using visual inspection or radiography, especially for high-pressure or safety-critical components.
We provide high-quality AISI 630 (17-4PH) stainless steel with reliable supply, competitive pricing, and professional technical support. To learn more about stock availability, custom sizes, or to request a quote, please:
Inquire Now: Contact our sales team for personalized assistance.
Add to Basket: Secure your order online for quick processing.
Our team is committed to delivering premium products that meet your exact specifications and project deadlines. Trust Qilu Steel for all your AISI 630 stainless steel needs.
AISI 630 (also known as 17-4PH) is a premium precipitation-hardening martensitic stainless steel renowned for its exceptional combination of high strength, superior corrosion resistance, and excellent mechanical properties. You can find its equivalent in different steel standards, such as: X5CrNiCuNb16-4/1.4542 from Europe standard EN 10088-3, 0Cr17Ni4Cu4Nb/05Cr17Ni4Cu4Nb from China standard GB/T 1220, SUS630 from Japan standard JIS G4303, 09X17H7Ю1 from Russia standard GOST 5632-72.
630 stainless steel offers exceptional hardness after heat treatment, good weldability, and resistance to stress corrosion cracking, making it suitable for high-performance applications. Whether you require robust components for aerospace missions, corrosion-resistant parts for oil and gas operations, or precision tools for medical use, AISI 630 stainless steel delivers reliable performance and long-lasting durability.
AISI 630 stainless steel has well-established equivalent grades in major global steel standards, ensuring consistency and compatibility across international projects.
Country | USA | EN | China | Japan | Russia |
Standard | ASTM A693 | EN10088-3 | GB/T1220 | JIS G4303 | GOST 5632-76 |
Grade | 630/17-4PH | X5CrNiCuNb16-4/1.4542 | 05Cr17Ni4Cu4Nb | SUS630 | 09X17H7Ю1 |
The precise chemical composition of AISI 630 and its equivalent grades is critical to achieving their outstanding properties. All values are maximum limits unless specified as a range.
Grade | C | Si | Mn | P | S | Cr | Ni | Cu | Nb |
630 | 0.07Max | 1.0Max | 1.0Max | 0.040Max | 0.030Max | 15.00-17.50 | 3.00-5.00 | 3.00-5.00 | 0.15-0.45 |
X5CrNiCuNb16-4/1.4542 | 0.07Max | 0.7Max | 1.5Max | 0.040Max | 0.030Max | 15.00-17.00 | 3.00-5.00 | 3.00-5.00 | |
05Cr17Ni4Cu4Nb | 0.07Max | 1.0Max | 1.0Max | 0.040Max | 0.030Max | 15.00-17.50 | 3.00-5.00 | 3.00-5.00 | |
SUS630 | 0.07Max | 1.0Max | 1.0Max | 0.040Max | 0.030Max | 15.00-17.50 | 3.00-5.00 | 3.00-5.00 | |
09X17H7Ю1 | 0.09Max | 0.8Max | 0.8Max | 0.035Max | 0.025Max | 16.50-18.00 | 6.50-7.50 | / |
AISI 630 stainless steel’s mechanical performance is optimized through heat treatment, including solution annealing and precipitation hardening. Below are the key mechanical properties for major grades, as specified by their respective standards.
Grade | Heat treatment | Tensile strength | Yield strength | Alongation | Area of reduction | Hardness | |
0Cr17Ni4Cu4Nb | Solution Annealing | / | / | / | / | HBW363 Max | |
Age Hardening | 480℃ | 1310Mpa Min | 1180Mpa Min | 10% Min | 40% Min | HBW375 Min | |
550℃ | 1070Mpa Min | 1000Mpa Min | 12% Min | 45% Min | HBW331 Min | ||
580℃ | 1000Mpa Min | 865Mpa Min | 13% Min | 45% Min | HBW302 Min | ||
620℃ | 930Mpa Min | 725Mpa Min | 16% Min | 50% Min | HBW277 Min | ||
SUS630 | Solution Annealing | / | / | / | / | HBW363 Max | |
H900 | 1310Mpa Min | 1175Mpa Min | 10% Min | 40% Min | HBW375 Min | ||
H1025 | 1070Mpa Min | 1000Mpa Min | 12% Min | 45% Min | HBW331 Min | ||
H1075 | 1000Mpa Min | 860Mpa Min | 13% Min | 45% Min | HBW302 Min | ||
H1150 | 930Mpa Min | 725Mpa Min | 16% Min | 50% Min | HBW277 Min | ||
Steel grade | Thickness | HT condition | Tensile strength | Yield strength | Alongation | Impact value at RT/J | Hardness /HBW | ||
L | Tr | L | Tr | ||||||
X5CrNiCuNb16-4/1.4542 | 100mm Max | AT | 1200Mpa Max | / | / | / | / | / | 360Max |
P800 | 800-950Mpa | 520Mpa Min | 18% Min | / | 75J Min | / | / | ||
P930 | 930-1100Mpa | 720Mpa Min | 16% Min | / | 40J Min | / | / | ||
P960 | 960-1160Mpa | 790Mpa Min | 12% Min | / | / | / | / | ||
P1070 | 1070-1270Mpa | 1000Mpa Min | 10% Min | / | / | / | / | ||
AT=Solution annealed; P= Precipitation hardened
For X5CrNiCuNb16-4 / 1.4542, the minimum 0.2% proof strength at elevated temperatures is as follows:
Steel garde | HT condition | Minimum 0.2% proof strength at a temperature of: | ||||
100℃ | 150℃ | 200℃ | 250℃ | 300℃ | ||
X5CrNiCuNb16-4/1.4542 | Mpa or N/mm2 | |||||
P800 | 500 | 490 | 480 | 470 | 460 | |
P930 | 680 | 660 | 640 | 620 | 600 | |
P960 | 730 | 710 | 690 | 670 | 650 | |
P1070 | 880 | 830 | 800 | 770 | 750 | |
P= Precipitation hardened
We offer AISI 630 stainless steel in a wide range of product types, sizes, and surface finishes to meet your specific application needs. All products adhere to strict tolerance and straightness standards.
Product type | Size range | Length |
Hot rolled bar | Φ10-Φ130mm | 5000-7000mm |
Hot forged bar | Φ140-Φ600mm | 2000-5800mm |
Hot rolled plate/sheet | T:2-60mm; W:310-810mm | 6000-12000mm |
Hot forged plate | T:70-250mm; W:310-810mm | 2000-5800mm |
Hot Forged block | T: 260-500mm; W: 300-1000mm | 2000-5800mm |
Surface Finish | Turned | Milled | Grinding(Best) | Polished(Best) | Peeled(Best) | Black Forged | Black Rolled |
Tolerance | +0/+3mm | +0/+3mm | +0/+0.05mm | +0/+0.05mm | +0/+0.1mm | +0/+5mm | +0/+1mm |
Straighness | 1mm/1000mm max. | 3mm/1000mm max. | |||||
We maintain a large monthly stock of AISI 630 hot rolled bars and forged bars (over 10,000 tons) to ensure quick delivery. Below are common stock diameters:
Hot Rolled Bar Stock Diameters: 10mm, 12mm, 15mm, 18mm, 20mm, 22mm, 25mm, 28mm, 30mm, 32mm, 35mm, 38mm, 40mm, 45mm, 50mm, 55mm, 60mm, 65mm, 70mm, 75mm, 80mm, 85mm, 90mm, 95mm, 100mm, 105mm, 110mm, 120mm, 130mm, 140mm, 150mm, 160mm, 170mm, 180mm, 190mm
Hot Forged Bar Stock Diameters: 200mm, 210mm, 220mm, 230mm, 240mm, 250mm, 260mm, 270mm, 280mm, 290mm, 300mm, 310mm, 320mm, 330mm, 340mm, 350mm, 360mm, 370mm, 380mm, 390mm, 400mm
Stock levels change daily. For real-time availability, please contact our sales team.
All AISI 630 stainless steel products undergo ultrasonic testing in accordance with EN 10228-3 Class III or Sep 1921-84 D/D standards to ensure no internal defects, guaranteeing structural integrity.
We utilize advanced steel making technologies to produce high-purity AISI 630:
EF + LF + VD
EAF + LF + VD
EF + LF + VD + ESR
EAF + LF + VD + ESR
Hot forging temperature: 900℃ - 1150℃
Cooling method: Furnace cooling or air cooling (to prevent cracking and ensure uniform properties)
AISI 630 performance is enhanced through precise heat treatment processes:
Solution Annealing: Heat to 1020℃ - 1060℃, followed by rapid cooling (air or water) to achieve a uniform microstructure.
Precipitation Hardening:
480℃: After solution treatment, heat to 470℃ - 490℃, air cool
550℃: After solution treatment, heat to 540℃ - 560℃, air cool
580℃: After solution treatment, heat to 570℃ - 590℃, air cool
620℃: After solution treatment, heat to 610℃ - 630℃, air cool
High Strength: Achieves exceptional tensile and yield strength through precipitation hardening, outperforming many conventional stainless steels.
Superior Corrosion Resistance: Resists corrosion in mild acids, alkalis, saltwater, and atmospheric environments, suitable for harsh operating conditions.
Good Weldability: Can be welded using standard methods (with proper pre- and post-weld heat treatment to maintain properties).
Stress Corrosion Cracking Resistance: Exhibits excellent resistance to stress corrosion cracking, critical for high-pressure and corrosive environments.
Excellent Machinability: Easy to machine, grind, and form, reducing production time and costs.
Heat Treatable: Customizable mechanical properties via different heat treatment cycles to match specific application requirements.
AISI 630 stainless steel’s unique combination of properties makes it ideal for the following industries and components:
1. Aerospace
Aircraft components: Landing gear parts, engine fasteners, turbine blades, and structural components.
Aerospace equipment: Rocket engine shells, satellite structures, and spacecraft hardware.
2. Oil & Energy Industry
Oil/gas equipment: Valves, pump shafts, downhole tools, and wellhead components.
Nuclear power: Reactor internal fasteners, control rod drive mechanisms, and pressure vessel parts.
3. Chemical & Marine Engineering
Chemical equipment: Acid-resistant pumps, agitator shafts, reaction vessel liners, and piping systems.
Marine environment: Ship shaft systems, propeller shafts, desalination equipment, and offshore platform components.
4. Machinery Manufacturing & Tools
High-stress parts: Gears, bearings, mold inserts, and precision mechanical components.
Medical equipment: Surgical tools, orthopedic implants (e.g., hip and knee replacements), and dental instruments (biocompatible and corrosion-resistant).
AISI 630 is a precipitation-hardening martensitic stainless steel, while 304 is an austenitic stainless steel. Key differences include:
Strength: AISI 630 offers significantly higher tensile/yield strength (up to 1310 Mpa after heat treatment) compared to 304 (around 515 Mpa).
Heat Treatment: AISI 630 can be strengthened via precipitation hardening, while 304 cannot be hardened by heat treatment (only work-hardened).
Corrosion Resistance: 304 has better general corrosion resistance in mild environments, but AISI 630 excels in stress corrosion cracking resistance and performs well in moderate corrosive conditions.
Applications: AISI 630 is used for high-stress, high-performance parts, while 304 is suitable for general-purpose, low-stress applications.
Yes, AISI 630 is weldable using common methods like GTAW (TIG), GMAW (MIG), and SMAW (stick welding). Critical precautions:
Avoid welding in the hardened state; weld in the solution-annealed condition whenever possible.
Use low-heat input to prevent grain growth and maintain mechanical properties.
Post-weld heat treatment (solution annealing + precipitation hardening) is recommended to restore strength and corrosion resistance, especially for critical components.
Use matching filler metals (e.g., ER630 for GTAW/GMAW) to ensure compatibility.
The optimal heat treatment depends on your application:
High Strength: H900 (480℃ aging) – Achieves the highest tensile strength (1310 Mpa min) but lower toughness, ideal for static-loaded components like fasteners.
Balanced Strength & Toughness: H1025 (550℃ aging) or H1075 (580℃ aging) – Offers moderate strength (1000-1070 Mpa min) and improved elongation/impact resistance, suitable for dynamic-loaded parts like gears or shafts.
Maximum Toughness: H1150 (620℃ aging) – Lower strength (930 Mpa min) but highest ductility (16% min elongation), ideal for components requiring shock resistance.
Yes, AISI 630 exhibits excellent corrosion resistance in marine environments, including saltwater and humid coastal atmospheres. It resists pitting, crevice corrosion, and stress corrosion cracking, making it ideal for marine components like ship shafts, propeller parts, and desalination equipment. For extreme marine conditions (e.g., prolonged submersion in highly corrosive water), we recommend periodic maintenance and surface protection (e.g., passivation) to extend service life.
AISI 630 can operate reliably at temperatures up to 315℃ (600°F) for continuous use. At temperatures above 315℃, its mechanical strength (especially yield strength) gradually decreases, and long-term exposure may affect corrosion resistance. For high-temperature applications (315℃+), consult our technical team to evaluate feasibility or explore specialized heat treatment options.
The choice of surface finish depends on your application:
Black Forged/Black Rolled: Cost-effective, suitable for non-critical components or parts that will be further machined.
Turned/Milled: For general-purpose components requiring moderate precision (tolerance +0/+3mm).
Peeled: Improved surface smoothness (tolerance +0/+0.1mm), ideal for shafts or cylindrical parts.
Ground/Polished: Highest precision (tolerance +0/+0.05mm) and smoothness, suitable for critical components like medical implants, precision gears, or high-pressure valves.
Store AISI 630 products in a dry, well-ventilated area to prevent moisture buildup and corrosion. Avoid contact with corrosive substances (e.g., acids, alkalis, or salt) during storage.
Use clean, non-abrasive tools for handling to prevent surface scratches. Scratches can create crevice corrosion sites, so promptly repair minor scratches with a stainless steel polish or passivation treatment.
For long-term storage (6 months+), apply a thin layer of anti-corrosion oil or wrap in moisture-resistant packaging.
Use high-speed steel (HSS) or carbide tools for machining AISI 630. Carbide tools are recommended for higher efficiency and longer tool life.
Maintain a cutting speed of 100-150 m/min (for turning) and 50-100 m/min (for milling) to minimize heat buildup, which can affect material properties.
Use cutting fluids (e.g., mineral oil or water-soluble coolants) to reduce friction and cool the workpiece, improving surface finish and tool life.
Avoid excessive cutting forces, as AISI 630’s high strength can cause tool wear or workpiece deformation.
Passivation: After machining or welding, perform passivation treatment (using nitric acid or citric acid solutions) to enhance corrosion resistance by forming a protective oxide layer on the surface.
Cleaning: Regularly clean AISI 630 components with mild soap and water or a stainless steel cleaner. Avoid abrasive cleaners (e.g., steel wool) that can scratch the surface.
Inspection: Periodically inspect components for signs of corrosion (e.g., pitting, discoloration) or wear. For critical applications, conduct non-destructive testing (e.g., ultrasonic or visual inspection) annually.
After welding, remove weld spatter and slag using a wire brush or grinder.
Perform post-weld heat treatment (solution annealing + precipitation hardening) to restore strength and corrosion resistance.
Inspect welds for defects (e.g., cracks, porosity) using visual inspection or radiography, especially for high-pressure or safety-critical components.
We provide high-quality AISI 630 (17-4PH) stainless steel with reliable supply, competitive pricing, and professional technical support. To learn more about stock availability, custom sizes, or to request a quote, please:
Inquire Now: Contact our sales team for personalized assistance.
Add to Basket: Secure your order online for quick processing.
Our team is committed to delivering premium products that meet your exact specifications and project deadlines. Trust Qilu Steel for all your AISI 630 stainless steel needs.
