17-4 PH Hex Cap Screws
An extremely strong precipitation hardened stainless steel
Well suited for high strength applciaitons
Up to 4x stronger than 316 stainless steel
Maintains its mechanical strength up to 600°F
17-4 PH Chemistry & Specifications
17-4 PH hex head cap screw features and benefits
17-4PH Datasheet
17-4 PH hex head cap screws are made from a precipitation hardened stainless steel most known for its exceptional strength and its ability to maintain its mechanical properties to 600°F. Compared to 316 stainless steel, 17-4 PH hex head cap screws yield strength is up over 4 times greater. When compared to Duplex 2205 screws, the yield strength of 17-4 PH can be up to 2-½ times greater.
17-4 hex head cap screws are available in 8 different aged (precipitation hardened) conditions offering a variety of mechanical properties.
Resources: 17-4PH Torque Specs
17-4 PH Screw Types: 12 Point Screws, Button Head Cap Screws, Flat Head Screws, Hex Cap Screws, Pan Head Screws, Set Screws, Socket Head Cap Screws, Tamper Resistant Security Screws, Torx Screws, Vented Screws
17-4 PH Hex Head Cap Screw Features and Benefits
It is important to differentiate between a 17-4 PH hex head cap screw and hex head bolt. Often people assume they are the same, but they are actually very different fasteners in terms of how they are manufactured, as well as from an application perspective. Regardless of your choice, 17-4 PH hex heads offer strong, stable joints because of their large head service.
The Hex Comparison
Hex Head Cap Screw | Hex Head Bolts |
Precise applications where tight tolerances on the body dimensions are required. Features flat washer facing under the bolt head. Also called a finished hex bolt.
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17-4 PH Hex Head Cap Screw Advantages
The most important feature of a 17-4 PH hex head cap screws is that it has a larger bearing surface area which provide better clamping pressure than other type of fastener such as a socket head cap screw. Additionally, since debris build up is less of an issue with this style of fastener verses a socket head cap screw, they are ideal of dirty applications where particles could clog up a socket. Though 17-4 PH socket heads are typically used for tight access applications, hex heads can be a better choice when there is only side clearance available for tightening.
17-4PH Chemistry & Specifications
17-4PH Specifications: UNS S17400, AISI 630, ASTM A564-630, Werkstoff 1.4542, AMS 5604 Sheet, Strip and Plate, ASTM A 693 Plate
17-4PH | Fe | Cr | Ni | Cu | Mn | Si | Mo | Nb+Ta | C | P | S |
Min% |
| 15.0 | 3.0 | 3.0 | - | - | - | - | - | - | - |
Max% | Bal | 17.5 | 5.0 | 5.0 | 1.0 | 1.0 | 0.50 | 0.45 | 0.07 | 0.04 | 0.03 |
ASTM F593, Grade 630
This specification covers seven groups of stainless steel alloys, with ASTM F593, Grade 630 applying 17-4PH. ASTM F593 Grade 630 covers the requirements for 17-4PH stainless steel bolts, hex cap screws, and studs sized 0.25 to 1.50 inches, inclusive, in nominal diameter. It is intended for common use and for service applications requiring general corrosion resistance.
| Full-Size Tests | Machined Specimen Tests |
Stainless Steel Alloy Group | Condition | Alloy Mechanical Property Marking | Nominal Diameter (inches) | Tensile Strength (ksi) | Yield Strength (ksi) | Rockwell Hardness | Tensile Strength (ksi) | Yield Strength | Elongation % |
7(630) | AH | F593U | 1/4 to 1.5 IN | 135 to 170 | 105 | C28 to38 | 135 | 105 | 16 |
Common 17-4 Fastener Conditions: Aged Conditions vs Tensile Strength
Aged Condition | Ultimate Tensile (ksi) | Yield Strength at 0.2% Offset (ksi) | Elongation % | Hardness Rc |
H900 | 200 | 185 | 14 | 40-47 |
H925 | 190 | 175 | 14 | 38-45 |
H1025 | 170 | 165 | 15 | 35-42 |
H1075 | 165 | 150 | 16 | 33-39 |
H1100 | 150 | 135 | 17 | 32-38 |
H115C | 145 | 125 | 19 | 28-37 |
H1150-M | 125 | 85 | 22 | 26-36 |
Annealed | 160 | 145 | 5 | ~35 |