630,17-4PH... Precipitation-hardening martensitic stainless steel is used for shafts, gears, valve cores and other components that require wear resistance and high stress resistance.

630 stainless steel and 17-4PH are actually the same material (UNS S17400), only with different designations—the former is the standard grade under the American AISI specification, while the latter is a common commercial name. It is a precipitation-hardening stainless steel, with the key characteristics of extremely high strength and corrosion resistance comparable to 304. Let’s break down its core properties: · Mechanical Properties (Standout Feature): Through simple heat treatment (solution treatment + aging), its hardness can reach above HRC 40 (twice as hard as 316L), and its tensile strength exceeds 1000 MPa (equivalent to high-strength alloy steel). This is what fundamentally distinguishes it from ordinary stainless steel.· Corrosion Resistance: Superior to 410 (martensitic stainless steel) and comparable to 304. It performs excellently in marine atmospheres, weak acids, and most industrial environments, but must never be used in strong acids (such as hydrochloric acid) or high-temperature, high-pressure hydrogen sulfide environments (risk of stress corrosion cracking).· Physical Properties: Magnetic (unlike non-magnetic 304/316), with minimal distortion during heat treatment, making it highly suitable for precision machining. -What industries is it mainly used in? Precisely due to the combination of "steel strength + stainless steel corrosion resistance", it has become a "versatile high-strength component" across multiple fields:· Aerospace (Core Application): Aircraft actuators, landing gear components, high-speed connectors (replacing part of titanium alloys to reduce costs).· Petrochemical and Nuclear Power (Major Application): High-pressure valves, pump shafts, turbine blades (erosion-resistant), and nuclear waste treatment equipment.· Food and Medical Devices: Injection molding machine screws, food cutting tools (wear-resistant and rust-proof), surgical instruments.· Molds and General Machinery: Long-term replacement for chrome-plated parts, used as highly wear-resistant bushings, gears, and fixtures. 630 stainless steel and 17-4PH are actually the same material (UNS S17400), only with different designations—the former is the standard grade under the American AISI specification, while the latter is a common commercial name. It is a precipitation-hardening stainless steel, with the key characteristics of extremely high strength and corrosion resistance comparable to 304. Let’s break down its core properties: · Mechanical Properties (Standout Feature): Through simple heat treatment (solution treatment + aging), its hardness can reach above HRC 40 (twice as hard as 316L), and its tensile strength exceeds 1000 MPa (equivalent to high-strength alloy steel). This is what fundamentally distinguishes it from ordinary stainless steel.· Corrosion Resistance: Superior to 410 (martensitic stainless steel) and comparable to 304. It performs excellently in marine atmospheres, weak acids, and most industrial environments, but must never be used in strong acids (such as hydrochloric acid) or high-temperature, high-pressure hydrogen sulfide environments (risk of stress corrosion cracking).· Physical Properties: Magnetic (unlike non-magnetic 304/316), with minimal distortion during heat treatment, making it highly suitable for precision machining. ---What industries is it mainly used in? Precisely due to the combination of "steel strength + stainless steel corrosion resistance", it has become a "versatile high-strength component" across multiple fields: · Aerospace (Core Application): Aircraft actuators, landing gear components, high-speed connectors (replacing part of titanium alloys to reduce costs).· Petrochemical and Nuclear Power (Major Application): High-pressure valves, pump shafts, turbine blades (erosion-resistant), and nuclear waste treatment equipment.· Food and Medical Devices: Injection molding machine screws, food cutting tools (wear-resistant and rust-proof), surgical instruments.· Molds and General Machinery: Long-term replacement for chrome-plated parts, used as highly wear-resistant bushings, gears, and fixtures. -Key Precautions · Heat Treatment Is Essential: The material in its as-supplied condition (solution-treated state) is not hard (approximately HRC 28–32). It must undergo aging treatment to achieve high hardness; otherwise, its performance will be severely compromised.· Machining Difficulty: Machining becomes challenging after age hardening. It is generally recommended to perform machining in the solution-treated state, followed by final heat treatment for stabilization.· Price: Approximately 30%–50% more expensive than 316L, but its overall performance delivers exceptional cost-effectiveness. If you are manufacturing valve spindles or mold ejector pins, the H900 aging condition (maximum hardness) is recommended directly; for welding and assembly, the H1150 condition (optimal overall toughness) should be selected. You can inform me of the specific service environment (operating temperature, contact media) and stress type, and I will help confirm the appropriate heat treatment condition. Key Precautions · Heat Treatment Is Essential: The material in its as-supplied condition (solution-treated state) is not hard (approximately HRC 28–32). It must undergo aging treatment to achieve high hardness; otherwise, its performance will be severely compromised.· Machining Difficulty: Machining becomes challenging after age hardening. It is generally recommended to perform machining in the solution-treated state, followed by final heat treatment for stabilization.· Price: Approximately 30%–50% more expensive than 316L, but its overall performance delivers exceptional cost-effectiveness. If you are manufacturing valve spindles or mold ejector pins, the H900 aging condition (maximum hardness) is recommended directly; for welding and assembly, the H1150 condition (optimal overall toughness) should be selected. You can inform me of the specific service environment (operating temperature, contact media) and stress type, and I will help confirm the appropriate heat treatment condition.