Overview

A custom 301 stainless steel diaphragm is made by photochemical machining, a stress-free route that images the diaphragm profile, corrugations and any relief slots onto dry-film resist laminated to spring-temper 301 sheet, then dissolves the unprotected metal in a chemistry tuned to austenitic stainless steel. Profile, thickness-related flexure and edge quality are set by the artwork and etch dwell rather than punch force, so the thin, high-strength foil is cut without burrs, work hardening or the distortion that blanking causes. Grade 301 (17Cr-7Ni / 1.4310) is cold-rolled to high spring properties, supplied in 0.02–0.3 mm gauges, and optionally paired with 304/316L for mixed builds.

For sensor and fluid-control buyers, a custom 301 stainless steel diaphragm solves three recurring problems. Spring-temper 301 is strong and hard, so stamping thin profiles curls the part, drags the edge and wears dies quickly; pressure diaphragms need tight profile tolerance, uniform thickness and repeatable flexure that mechanical cutting struggles to hold at 0.05 mm scale; and the cold-worked spring properties, the reason 301 is chosen, must not be lost to heat-affected zones. Chemical machining forms every feature at one time, keeping stiffness and deflection consistent from first article through volume, while the burr-free edge resists fatigue cracking under cyclic pressure. New profiles need only a new film.

Parameter Window

• Available Materials: 301 (1.4310 / SUS301), 301SH high-strength temper; also 304/316L stainless for mixed builds
• Material Thickness Range: 0.02–0.3 mm (common 0.05 / 0.1 / 0.2 mm)
• Tolerance: ±0.01 mm on profile, ±0.01 mm on thickness, ±0.02 mm on corrugation position
• Minimum Feature: 0.05 mm slot, 0.08 mm web, 0.12 mm relief hole
• Surface Options: nitric passivation, electropolishing, deburring, matte finish, ultrasonic cleaning
• Compliance: ISO 9001 process control, RoHS/REACH material traceability

Manufacturing Process / Workflow (8 Steps)

1. Artwork & Nesting — Vectorize the diaphragm profile and corrugations, allow for etch undercut, and plan panel layout with tie bars and registration marks.
2. Material Certification & Prep — Verify 301 temper, tensile strength and thickness, inspect for scratches and flatness, then shear to exposure size.
3. Cleaning & Lamination — Degrease and laminate dry-film resist under matched heat and pressure so no bubbles sit under fine webs.
4. UV Exposure — Expose through high-resolution film with the profile registered to the sheet edge for panel-level consistency.
5. Development — Wash out unexposed resist to open the cut areas and inspect for residue that would block etching.
6. Controlled Etching — Spray stainless-matched chemistry, tuning time, temperature and conveyor speed to hold sidewalls and avoid edge ragging.
7. Stripping & Finishing — Remove resist, neutralize, then passivate, electropolish and deburr to protect fatigue life and surface finish.
8. Inspection & Packaging — Measure profile, thickness and flatness on a vision system, verify flexure on a sample, then pack in clean trays.

Core Advantages

1. Burr-free fatigue-resistant edges: Chemical removal leaves no dragged edge or notch, so cyclic pressure loading is far less likely to start a fatigue crack.
2. No die cost: Each new diaphragm profile is a new film, keeping prototypes and frequent revisions economical without a blanking tool.
3. High spring strength: Cold-rolled 301 delivers high yield strength and elastic return in a thin, lightweight diaphragm.
4. Repeatable flexure: 0.05 mm slots and fine corrugations form together across a panel with tight profile spread and uniform stiffness.
5. Stress-free flatness: With no shear or heat input, spring-temper foil keeps its cold-worked properties and stays flat for clamping.
6. Fast profile tuning: With a custom 301 stainless steel diaphragm, profile, thickness and corrugation can be tuned item by item to a target pressure range and deflection.

Typical Applications

• Pressure sensor diaphragms: Sensing elements whose deflection is calibrated to a pressure range in transmitters and transducers.
• Pressure switches: Snap-action and threshold diaphragms that must return repeatably over many cycles.
• Valve and regulator membranes: Control diaphragms for gas and liquid regulators requiring long fatigue life.
• Pump diaphragms: Metering and dosing pump membranes that combine spring strength with corrosion resistance.
• Burst discs and relief plates: Calibrated rupture elements where consistent thickness sets the burst pressure.
• Actuator and spring plates: Thin elastic plates for micro-actuators and precision mechanisms.

Design Notes & Process Considerations

1. Feature-to-thickness ratio: Keep slots and webs at or above material thickness; too fine a feature distorts from undercut and weakens fatigue life.
2. Profile and flexure callout: State profile tolerance, thickness and target deflection or pressure range, and define corrugation geometry rather than only a part number.
3. Temper and strength selection: Specify 301 temper and tensile range, note rolling direction, and state certificate needs for spring properties.
4. Nesting and tie bars: Leave enough tie bars and process borders, and specify the final cut method so thin webs survive stripping and cleaning.
5. Thin-foil handling: For foil below 0.05 mm, specify a carrier or liner and call out flatness and cleanliness to avoid creases and fingerprints.
6. Surface and fatigue control: With a custom 301 stainless steel diaphragm, define electropolish, passivation and edge-finish limits, especially for high-cycle duty.