17-4 PH Flat washers
ISO 7089 / ISO 7090ASTM A693
For 17-4 PH washers, aging-controlled strength and hardness is only useful with a bearing section that stays flat under load. Bore, outside diameter and thickness match the head or nut to the supported member.
- MOQ
- 100PCS
- Samples · typical
- ~20 days
- Production · typical
- 25–35 days
- Heat treatment
- Solution treated (Condition A) / Age hardened H900 / Age hardened H1025 / Age hardened H1150
EN 10204 3.1 MTC + heat-number traceability
Which standard is on your order?
Raw Material Specifications
Dimension Reference
Heat Treatment
Solution treated, then aged to the specified H conditionCondition A is the solution-treated starting state; aging to H900, H1025 or H1150 sets the final strength–toughness balance.
What we can make in 17-4 PH
Normal series
Use under bolt heads and nuts on machined equipment faces with adequate surrounding seat area. The bore must clear the bolt shank and under-head radius so the washer lies flat.
Larger outside diameter
Use over slots, oversized holes and softer mounting surfaces to spread the bearing load. Washer thickness matters as well as diameter: a thin wide washer can dish over an unsupported opening.
Square & special profiles
Use on channel supports, slotted bases and special mounting pads where a round washer leaves insufficient support. Profile and hole position keep the bearing plate seated across the actual opening.
- Geometry
- Bore × outside diameter × thickness
- Forms
- Round · Square · Drawing profiles
- Function
- Bearing surface · Spacing
- Sizing
- Metric · Inch
- Final condition
- Solution treated (Condition A) · Age hardened H900 · Age hardened H1025 · Age hardened H1150
- Inspection
- Bore · Outside diameter · Thickness · Burrs
Manufacturing route
Small lots can be machined from suitable stock; repeat production uses cut or punched blanks with bore and outer edge finishing.
Heat treatment & final condition
Solution treatment and the specified aging condition are recorded against the production lot; final dimensions are checked after thermal processing.
Finished geometry
Final condition and hardness are chosen for bearing load, then flatness and parallel faces are checked after thermal processing.
Where 17-4 PH fits — and what matters
Industrial Machinery & Automation
Machine frames and positioning fixtures17-4 PH flat washers spread bolt or nut bearing load across machine frames and positioning fixtures, protecting the seating surface and bridging the specified hole clearance. Alignment, operating cycles and replacement access define the working interface.
Automotive & EV Manufacturing Equipment
Assembly fixtures and test-rig frames17-4 PH flat washers spread bolt or nut bearing load across assembly fixtures and test-rig frames, protecting the seating surface and bridging the specified hole clearance. Repeated tooling changes require consistent seating and repeatable assembly dimensions.
Pumps, Valves & OEM
Actuator mounts and pump baseplates17-4 PH flat washers spread bolt or nut bearing load across actuator mounts and pump baseplates, protecting the seating surface and bridging the specified hole clearance. Repeated maintenance makes fit, engagement and access part of the component specification.
Same washer. Different material priorities.
17-4 PH material data316L
Molybdenum-bearing stainless performance in wet equipment.
- Connection priority
- Bearing pressure and resistance to dishing
- Washdown and retained cleaner
- Cleaner concentration, rinse quality and deposits determine the exposure in covered joints. The low-carbon designation does not independently establish a fastener strength class. Include liquid retained at the two bearing faces and the bore around the shank in the exposure description.
Inconel 625
Solid-solution strength and resistance to aggressive process liquids.
- Connection priority
- Bearing pressure and resistance to dishing
- Annealed or solution-annealed 625
- The delivery condition affects strength and high-temperature response. Keep the specified condition with the component’s mechanical acceptance; 718-style aging is not the strengthening route for 625. Include liquid retained at the two bearing faces and the bore around the shank in the exposure description.
Duplex 2205
Duplex strength and chloride-corrosion resistance.
- Connection priority
- Bearing pressure and resistance to dishing
- S31803 or S32205
- The specified UNS fixes the chemistry. Solution treatment, section size and the ordered mechanical or corrosion tests establish the final duplex condition. Include liquid retained at the two bearing faces and the bore around the shank in the exposure description.
From drawing to documented delivery
- 01Drawing & BOMForm, dimensions and quantity
- 02Material & formingGrade, heat and manufacturing route
- 03Final inspectionGeometry, threads and ordered tests
- 04Documents & dispatchLot records and identified packing
Order documents
- Material identity
- UNS S17400 · heat number · ordered condition
- Final-part acceptance
- Lot-linked aging record and mechanical acceptance in the final condition.
- Dimensional record
- Bore · Outside diameter · Thickness · Burrs
- Traceability
- EN 10204 3.1 material certificate · production lot · identified packing
Build your 17-4 PH washer enquiry
Questions about 17-4 PH flat washers
Should the washer use the same alloy as the bolt?
The wetted assembly may need matching corrosion resistance, but the washer also needs sufficient bearing strength and thickness. The bolt grade does not by itself specify a hardened or load-rated washer.