In the food processing and packaging industry, the correct selection of materials for equipment components directly affects food safety, equipment service life, and production efficiency. After all, the food processing environment is special, with high moisture, acid-base corrosion being common, as well as high-intensity physical wear. Therefore, materials must have excellent corrosion resistance and mechanical properties.
This article focuses on several common types of stainless steel used in the food industry and discusses tungsten carbide (cemented carbide) as a high-performance alternative. By comparing core dimensions such as hardness, wear resistance, and corrosion resistance, it provides an intuitive reference for you when selecting materials for food-grade cutting, homogenization, and filling components.
I. 3 Core Requirements for Food-Grade Materials (Must Meet)
When selecting food-contact materials, first meet these 3 basic conditions to avoid pitfalls:
- Non-toxic and harmless: Material components must not migrate harmful substances into food and must comply with food contact hygiene standards;
- Corrosion resistance: Capable of withstanding organic acids, salts in food, and chemical reagents used during cleaning;
- Easy-to-clean surface: Dense material structure, not easy to breed bacteria or leave food residues.
II. Performance Comparison Table of Common Stainless Steels for Food Machinery
Stainless steel is the basic material for food machinery. These three types are most commonly used, and the core information is organized into a table for quick understanding:
| Stainless Steel Type | Typical Grade | Core Features | Core Advantages | Application Scenarios |
|---|---|---|---|---|
| General-Purpose Austenitic Stainless Steel | 304 | Balanced comprehensive performance, easy to process | Low cost, strong oxidation resistance | Storage tanks, conveyor frames, non-load-bearing casings |
| Corrosion-Resistant Austenitic Stainless Steel | 316L | Added molybdenum element based on 304 | Excellent resistance to chloride corrosion (e.g., salt water), high hygiene level | Pipes and core valves for high-salt condiments, strong acidic juice processing |
| High-Hardness Martensitic Stainless Steel | 420/440 Series | Hardness can be improved through heat treatment | Good sharpness retention | Food cutting blades, crusher parts |
III. Tungsten Carbide (Cemented Carbide): A High-Performance Alternative in the Food Industry
Although the above-mentioned stainless steels are commonly used, their service life is often insufficient under extreme working conditions (such as high-pressure homogenization, ultra-hard material crushing). At this time, tungsten carbide, a “super-hard material”, comes into play.
⚠️ Key Reminder: When using tungsten carbide in the food industry, prioritize nickel-binder tungsten carbide instead of traditional cobalt-binder ones. There are two reasons: first, nickel-binder alloys have better corrosion resistance; second, they comply with food contact material hygiene standards in more countries.
IV. Comprehensive Performance Comparison Table of Core Materials (For Quick Selection)
The key indicators of common materials are summarized here. You can directly refer to it when selecting materials without comparing them one by one:
| Material Type | Typical Grade | Hardness (HRA/HRC) | Corrosion Resistance | Wear Life | Relative Cost |
|---|---|---|---|---|---|
| Austenitic Stainless Steel | 316L | Low (HRC < 20) | Extremely High | Low | Medium-Low |
| Martensitic Stainless Steel | 440C | Medium-High (HRC 55-60) | Medium | Medium | Medium |
| Nickel-Binder Tungsten Carbide | YN Series | Extremely High (HRA 88-91) | High | Extremely High | High |
V. Selecting Materials by Process: Precise Matching Without Waste
There is no best material, only the most suitable one for a specific process. Select according to core needs to ensure performance and control costs:
1. Core Need: Hygiene and Rust Prevention
- Application Scenarios: Pumps and pipes for conveying soy sauce, vinegar, high-salt sauces
- Recommended Material: 316L stainless steel (highest cost-performance ratio, meets corrosion resistance requirements)
2. Core Need: Cutting Efficiency and Sharpness
- Application Scenarios: Slicing frozen meat, fruit and vegetable slicing
- Conventional Choice: 440C series stainless steel
- High-Efficiency Upgrade Option: Tungsten carbide insert blades (for large-scale automated production, significantly reducing tool change frequency)
3. Core Need: High-Pressure Erosion Resistance
- Application Scenarios: Valve cores of food homogenizers, nozzles of high-pressure spray drying
- Recommended Material: Nickel-binder tungsten carbide (almost the only choice that can meet the working conditions)
VI. Material Maintenance Suggestions (Must-Read for Extending Service Life)
Selecting the right material is not enough; proper maintenance can maximize its service life. Remember these 3 points:
- Stainless steel parts: After welding, pay attention to heat treatment, or directly choose low-carbon grades (such as 316L) to prevent intergranular corrosion;
- Tungsten carbide parts: High hardness but higher brittleness than stainless steel. Avoid severe collisions with hard floors or tools during cleaning and installation;
- General Note: When selecting cleaning agents, confirm that alkalis and acids are within the material’s tolerance range to avoid corrosion caused by improper use.
Summary
In food processing equipment, 304/316L stainless steel provides basic hygiene guarantees, and 420/440 stainless steel meets basic cutting needs. However, as production efficiency requirements continue to increase, tungsten carbide shows unparalleled advantages in core high-wear components due to its super strong wear resistance.
Core Principle: Matching materials according to process requirements can not only ensure food safety but also reduce the cost of equipment shutdown and maintenance, achieving the highest cost-performance ratio.
Post time: Jan-21-2026
