Spring steel stamping delivers strength, flexibility, and good fatigue resistance, which is why it is used in products like automotive clips and industrial fasteners. However, it is not always simple to work with. To achieve consistent quality, you must understand each process step and know how to fix problems without wasting time or material.
The field of spring steel stamping changes quickly. This guide explains the main processes, common challenges, and new ideas influencing modern spring parts. Reading further will give you a clearer view of how everything fits together.
What Is Spring Steel Stamping?
Spring steel stamping is a process that uses a press and a matched die set to cut and shape thin sheets or strips of spring steel. The die applies controlled pressure and movement to form the material. This process can perform several operations, including blanking, piercing, bending, coining, embossing, and drawing. For speed and consistent quality, manufacturers often feed the material from coils.
Engineers select spring steel grades based on strength and springback requirements. Common choices include high-carbon steels like 1075 or 1095, and stainless spring grades like 301. Some parts require heat treatment and tempering after forming, while others use pre-tempered material to reduce production steps.
The basic process follows a precise sequence. Choose the right grade and thickness. Blank the outline of the part. Form and coin any needed features. Remove burrs and perform stress relief. Apply a finish, such as passivation or plating. Finally, inspect the parts to ensure they meet specifications.
Properties and Types of Spring Steel
Spring steels must bend without breaking and return to shape every time. Below, we’ll break down the traits that make this possible and highlight the most used grades in stamping.
Key Characteristics of Spring Steel
- Spring steel has high yield strength, so it returns to its original shape after loading.
- It offers long fatigue life, allowing parts to withstand many cycles without cracking.
- The material shows springback after forming, so tooling must allow for elastic return.
- Trattamento termico increases strength and sets the temper. Pre-tempered strip can skip this step.
- Formability changes with carbon content and temper. Softer tempers bend more easily with less risk of cracking.
Common Grades and Alloys Used in Stamping
- SAE 1074 / 1075 (High-carbon): Good mix of strength and formability. Common in clips, clamps, and flat springs.
- SAE 1095 (High-carbon): Very high strength and hardness with excellent snap-back. It can crack if the bend radii are too tight.
- SAE 1050–1065 (High-carbon): Moderate carbon range for easier forming than 1095 while maintaining good spring qualities.
- 301 Stainless (1/4-hard to full-hard): Corrosion-resistant and work-hardens during forming. Suitable for clips, contacts, and latches.
- 17-7PH Stainless: Precipitation-hardening type with high strength after aging. Holds strength at higher temperatures; common in aerospace and precision parts.
- 410 / 420 Stainless (Martensitic): Hardenable and magnetic with better wear resistance than 301. Lower corrosion resistance compared to austenitic grades.
The Spring Steel Stamping Process
Spring steel stamping follows a clear path from raw coil to finished part. Below, we cover how the material is prepared, the basic process steps, and the main types of stamping used for spring parts.
Preparing Raw Material for Stamping
The process begins with selecting the right spring steel grade and thickness. The material usually comes in coils or flat strips. It must meet the spec for hardness, thickness tolerance, and surface condition.
Next, the coil is unrolled and flattened if needed. This removes any curve or camber that could affect accuracy. Some shops clean or lubricate the strip to reduce tool wear and improve part finish.
Step-by-Step Stamping Workflow
- Alimentazione del materiale: The coil feeds into the press using a straightener and feeder. This ensures steady movement and position.
- Blanking or Piercing: The press cuts out part shapes or holes with high force. Clean, burr-free edges matter here.
- Formare: The metal bends or forms into shape using matched punch and die sets. Springback must be accounted for in the die design.
- Secondary Forming: Extra bends or coining may follow in the same press stroke or a second station.
- Deburring and Cleaning: Sharp edges are removed. Parts are often cleaned for inspection or finishing.
- Trattamento termico: If the part was formed soft, it gets hardened and tempered to set its spring properties.
Types of Stamping Techniques
- Stampaggio progressivo: The most common for spring parts. A strip moves through a die with many stations. Each station adds a step—cutting, bending, forming—until the final part drops.
- Stampaggio di stampi composti: Performs multiple operations at one station. Useful for flat parts with features on one plane.
- Stampaggio a trasferimento: Moves the part from one station to the next with mechanical fingers. Allows complex shapes and deep draws.
- Cancellazione fine: Produces very smooth, precise edges. Ideal for parts with tight tolerances or visible surfaces.
Common Challenges in Stamping Spring Steel
Spring steel is strong and flexible, but stamping it brings unique issues. Below, we look at two main problem areas: tool life and part defects during forming.
Usura e manutenzione degli utensili
Spring steel is more complex than most sheet materials. This means more wear on punches and dies, and sharp edges dull faster. Coatings like TiN or carbide inserts can help, but tools still need frequent checks.
If tools wear unevenly, parts go out of spec. Cuts get rough, and bends lose accuracy. Press force rises. This strains the press and shortens its life. Shops must schedule tool maintenance often and monitor tool life by part count.
Lubrication also affects wear. Without enough lube, friction builds up fast, leading to galling or edge tearing. Too much lube, though, causes staining or cleanup problems. Getting the right balance matters.
Cracking, Wrinkling, and Defects
Cracks form when the metal can’t stretch or bend enough. This happens at sharp corners, tight radii, or where the part thins too much. Engineers may soften the steel before forming, or increase bend radii to fix this.
Wrinkling occurs when compression forces the metal to fold. It occurs in deep draws or wide flanges. Support in the die or better blank holder pressure helps prevent it.
Other defects include edge burrs, surface marks, or incomplete cuts. These often relate to dull tools, wrong die clearance, or uneven press force.
Typical Applications Across Industries
Spring steel stamped parts support many critical functions. Their strength, flexibility, and fatigue resistance are functional in high-load, high-cycle environments. Here’s how different industries use them.
Automotive
Automakers use stamped spring steel parts for clips, shims, parentesi, and retaining rings. These parts hold panels, route wiring, or secure trim pieces. Suspension systems use spring steel spacers and washers to manage loads.
Stamped spring parts are also used in seat frames, steering columns, and door mechanisms. Their durability under vibration and repeated stress is key. The ability to mass-produce these parts with tight tolerances keeps costs down.
Medico
Medical devices need small, clean, and precise components. Spring steel is used in surgical clips, dental tools, and needle guides. The parts must flex without breaking and return to shape every time.
Grades like 17-7 PH and 301 stainless are common here. They offer corrosion resistance and can be sterilized. Tight control over surface finish and edge quality is critical for safety.
Aerospaziale
Aerospace demands lightweight, high-strength parts that can handle extreme forces. Spring steel is used in control linkages, fasteners, clamps, and vibration-damping systems.
The ability to absorb stress without permanent deformation helps in flight control systems and landing gear. Parts must meet strict standards for fatigue life and performance at different temperatures.
Industrial Tools
In industrial settings, spring steel stamped parts serve in hand tools, power tools, and machinery. Examples include snap rings, blade holders, detents, and safety latches.
These parts take repeated impacts and still hold their shape. The strength of spring steel keeps wear low and performance consistent, even under tough shop or field conditions.
Soluzioni e migliori pratiche
Stamping spring steel can run smooth with the proper setup and habits. These sections give simple ways to reduce defects, extend tool life, and improve output quality.
Process Adjustments to Reduce Defects
Use the proper die clearance. Spring steel needs more space between the punch and the die than softer metals. This keeps cuts clean and reduces edge cracking.
Apply an over-bend in tooling to offset springback. Test different angles during prototyping to find the best result. Don’t rely on one-size-fits-all settings.
Slow the press down slightly if cracks or wrinkles appear. A bit more time during forming helps the metal flow without damage.
Adjust raggio di curvatura. If cracks form at bends, increase the inside radius. The safe bend radius for spring steel is usually 1.5 to 2 times the thickness.
Lubrication and Material Handling Tips
Choose a lube made for high-strength steel. Look for ones with extreme pressure additives. These reduce friction, heat, and galling.
Apply just enough lubricant. Too much can cause slipping in the feeder, and too little leads to tool wear and surface scoring. Spray systems or rollers offer better control than manual application.
Keep coils clean and dry. Dirt or rust causes uneven feeding and can damage tools. Store material in a dry place, off the floor, and away from moisture.
Use proper straighteners and feeders. Spring steel has strong memory and may want to stay curved. A sound leveling system keeps it flat for consistent stamping.
Conclusione
Spring steel stamping is a wise choice for parts that need to flex, hold shape, and last. It supports fast production, consistent quality, and various designs. This process plays a key role across industries, from brackets in cars to clips in medical tools. With the right material, tooling, and setup, it delivers strong, repeatable results at scale.
Need help with custom spring steel stamped parts? We work with various grades, part types, and volumes. Whether you’re building prototypes or scaling production, let’s discuss how we can support your next project.
Ciao, sono Kevin Lee
Negli ultimi 10 anni mi sono immerso in varie forme di lavorazione della lamiera, condividendo qui le mie esperienze in diverse officine.
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Kevin Lee
Ho oltre dieci anni di esperienza professionale nella fabbricazione di lamiere, con specializzazione nel taglio laser, nella piegatura, nella saldatura e nelle tecniche di trattamento delle superfici. In qualità di direttore tecnico di Shengen, mi impegno a risolvere sfide produttive complesse e a promuovere innovazione e qualità in ogni progetto.
