Precision Stainless Steel Spring Strip

As a professional manufacturer of precision stainless steel spring strips in China, Qihong strictly controls thickness tolerances to within ±0.002mm and ensures a flatness superior to 0.05mm/m. We offer seven distinct hardness states—ranging from ANN to SH (160 HV to 600 HV)—to meet diverse application requirements. Utilizing high-quality stainless steel grades such as SUS301, our products feature a surface roughness of Ra ≤ 0.05μm, thereby satisfying the rigorous demands for high-precision elastic components in sectors such as consumer electronics and new energy vehicles. Choose Qihong to benefit from comprehensive, one-stop customization services—spanning from raw materials to finished products—along with rapid delivery.

Product Features

1. Extreme Precision, Controllable Dimensions: Equipped with professional precision rolling equipment, we stably produce ultra-thin spring strips with thickness tolerances strictly controlled within ±0.002mm; precision stretching and bending straightening processes eliminate internal stress in the material, resulting in flatness <0.05mm/m, completely solving problems such as warping and wavy edges, and meeting the stringent requirements of high-speed stamping and automated assembly.

2. Diverse Hardness, Adaptable Performance: Relying on mature heat treatment processes, we can provide seven hardness states: ANN (soft), 1/4H, 1/2H, 3/4H, H, EH (extra hard), and SH (super hard), with Vickers hardness covering 160HV-600HV, accurately matching the differentiated needs for elastic modulus, yield strength, and fatigue life in different scenarios.

3. High-Quality Surface, High Cleanliness:  Fine-grained control is implemented throughout the entire process, with surface roughness Ra value controlled below 0.05μm, free from scratches, pitting, and roller marks; various surface treatments are available, including 2B bright finish, BA mirror finish, 8K mirror finish, and brushed finish, balancing appearance and functional characteristics to meet the requirements of high-cleanliness application scenarios. 4. Excellent corrosion resistance and strong stability:  Made with high-quality austenitic stainless steel base material, the product exhibits outstanding corrosion resistance and can pass salt spray tests exceeding 1000 hours. It can adapt to extreme working conditions such as high humidity and extreme temperatures, ensuring long-term stable operation of the components, and meets environmental protection standards.

 

Product Parameters

Parameter Category	Specific Specifications
Core Material	Austenitic stainless steel such as SUS301 (1Cr17Ni7), SUS304 (0Cr18Ni9), SUS316 (0Cr17Ni12Mo2)
Thickness Range	0.03 mm-0.5 mm
Thickness Tolerance	Within ±0.002 mm
Flatness	<0.05 mm/m
Hardness State	ANN, 1/4H, 1/2H, 3/4H, H, EH, SH
Vickers Hardness Range	160HV-600HV
Surface Roughness	Ra≤0.05μm
Surface Treatment	2B bright finish, BA mirror finish, 8K mirror finish, brushed finish, matte finish, etc.
Width Range	5.0mm-1219mm (can be slit to any width, minimum step 0.1mm)
Applicable Standards	GB/T 4240, ASTM A666, JIS G4305

Product Applications

Based on its high precision, high elasticity, and high corrosion resistance, this product is widely used in high-end manufacturing fields such as consumer electronics, new energy vehicles, semiconductor photovoltaics, medical devices, and industrial automation. Core application scenarios include:

1. Consumer Electronics: Mobile phone SIM card tray springs, Type-C interface terminals, folding screen hinge components, camera motor springs, smart wearable device buckles, etc.;

2. New Energy Vehicles: Power battery flexible connectors, high-voltage connector terminals, charging pile contact pieces, automotive sensor elastic components, etc.;

3. Semiconductors and Photovoltaics: Chip testing probe card springs, photovoltaic junction box springs, precision relay contacts, etc.;

4. Medical Devices: Surgical forceps elastic components, endoscope precision components, core parts of dental tools, etc.;

5. Industrial Automation: Precision switch contacts, relay springs, miniature motor commutators, automation equipment detection springs, etc.

 

Why Choose Qihong?

1. Source Factory, Strong Capabilities: As a professional precision stainless steel processing enterprise in Ningbo, we possess complete cold rolling, heat treatment, and precision machining production lines.  Our steel grades cover the full range of 200 series, 300 series, and 400 series, allowing us to control quality from the raw material source.  Without intermediaries, we offer both quality and price advantages.

2. Strict Quality Control, Traceable Quality: Equipped with professional testing instruments and a team, we conduct comprehensive testing from raw material incoming inspection (including spectral analysis) to online monitoring during production, and finally to full testing of finished products (including hardness, corrosion resistance, and metallographic structure). Detailed material certificates are provided for each batch of products, ensuring product consistency and preventing defective products from leaving the factory.

3. Flexible Customization, Efficient Response: We support small-batch samples and large-scale mass production.  Based on customer drawings and requirements, we provide one-stop non-standard customization services, including material selection, hardness customization, and size slitting. Regular specifications are available in stock, and non-standard customized orders are delivered quickly. We also support JIT (Just-In-Time) logistics and delivery.

4. Professional Technology, Comprehensive Service: We have a senior technical team that can assist customers with material selection suggestions, stamping die optimization, and process problem solving. We have established a dedicated technical response channel and provide free sample trials. Our products are exported to many parts of the world, and we possess complete import and export qualifications and a logistics network.  Adhering to the philosophy of "cooperation, mutual assistance, and win-win," we establish long-term and stable cooperative relationships with our customers.