316SS Investment Casting -316SS (316 Stainless Steel) is a molybdenum-alloyed austenitic cast stainless steel, the most widely used corrosion-resistant casting grade after 304SS. It offers superior chloride and pitting corrosion resistance vs. 304, making it ideal for marine, chemical, and coastal applications.
International Standards & Equivalent Grades
| Standard | Grade Designation |
|---|---|
| ASTM (USA) | CF-8M (J92900) |
| EN (Europe) | 1.4408 / GX6CrNiMo18-10 |
| ISO | G-X6CrNiMo18-10 |
| Australian AS | CF8M / AS 4443-CF8M |
| Low Carbon Variant | 316L Cast: CF-3M (J92800) / 1.4435 |
Chemical Composition (Typical, %)
- Chromium (Cr): 16.0–18.0% (forms passive oxide layer)
- Nickel (Ni): 10.0–14.0% (stabilizes austenite)
- Molybdenum (Mo): 2.0–3.0% (key for chloride/pitting resistance)
- Carbon (C): ≤0.08% (316SS) / ≤0.03% (316L)
- Silicon (Si): ≤1.50%, Manganese (Mn): ≤2.0%
- Phosphorus (P): ≤0.045%, Sulfur (S): ≤0.030%
Key Properties
- Corrosion Resistance: Excellent resistance to pitting, crevice corrosion, and chloride attack (saltwater, chemicals).
- Mechanical (As-Cast / Annealed):
- Tensile Strength: ≥520 MPa
- Yield Strength: ≥205 MPa
- Elongation: ≥30%
- Hardness: ~180 HB
- Physical: Density ~7.98 g/cm³; non-magnetic; good weldability.
- Heat Resistance: Service up to ~870°C; prone to sensitization (carbide precipitation) 425–860°C.
Casting Processes
- Investment Casting (precision parts: valves, pumps, fittings)
- Sand Casting (larger components: housings, impellers)
- Centrifugal Casting (pipes, sleeves)
Typical Applications
- Marine: pumps, valves, fasteners, offshore hardware
- Chemical & Petrochemical: reactors, piping, tanks
- Food & Pharmaceutical: sanitary processing equipment
- Pulp & Paper, Desalination, Sewage Treatment
- Medical Instruments, Marine Hardware
316SS vs 316L Cast
- 316SS (CF-8M): Standard carbon (≤0.08%); good for general corrosion.
- 316L (CF-3M): Ultra-low carbon (≤0.03%); better post-weld corrosion resistance; preferred for welded assemblies
Advantages of 316 Cast Stainless Steel Over 304
316 cast stainless steel is an upgraded variant of 304, with the addition of molybdenum (Mo) as a key alloying element. This modification significantly enhances its performance, especially in harsh environments, making it a more reliable choice for demanding applications.
1. Superior Corrosion Resistance (Core Advantage)
- 316 contains 2.0%–3.0% molybdenum, while 304 has no molybdenum at all.
- Exceptional resistance to chloride ions, saltwater, seawater, and coastal salt spray—304 is prone to pitting, rusting, and corrosion in such environments.
- Stronger resistance to pitting corrosion, crevice corrosion, and attack from acidic, alkaline, and chemical media (e.g., industrial wastewater, chemical solutions).
- Maintains its passive oxide layer better than 304 in harsh corrosive conditions, ensuring long-term durability.
2. Better Adaptability to Marine & Coastal Environments
- 316 is the preferred grade for marine hardware, ship components, offshore equipment, and coastal engineering projects.
- 304 is only suitable for indoor use or mild atmospheric environments; it easily rusts when exposed to sea breeze, salt spray, or seawater.
3. Enhanced High-Temperature & High-Pressure Performance
- 316 offers better high-temperature strength, creep resistance, and oxidation resistance compared to 304.
- Ideal for high-temperature applications such as pipelines, valves, pump bodies, and petrochemical equipment operating in elevated temperature and pressure conditions.
4. Improved Weldability & Post-Weld Corrosion Resistance
- 316 (and its low-carbon variant 316L) exhibits superior post-weld corrosion resistance.
- Less susceptible to intergranular corrosion after welding, compared to 304, which is more prone to this issue when welded without proper post-weld heat treatment.
5. Wider Application Scope
316 is widely used in marine, chemical, petrochemical, food and pharmaceutical, desalination, sewage treatment, and pulp and paper industries. In contrast, 304 is limited to general civil use, indoor equipment, and non-corrosive industrial components.
6. Cast Grade Standard Correspondence
| Cast Material | ASTM Grade | EN Grade | ISO Grade |
|---|---|---|---|
| 304 Cast Stainless Steel | CF-8 (J92600) | 1.4308 / GX6CrNi18-9 | G-X6CrNi18-9 |
| 316 Cast Stainless Steel | CF-8M (J92900) | 1.4408 / GX6CrNiMo18-10 | G-X6CrNiMo18-10 |
Summary
The key advantage of 316 over 304 lies in the addition of molybdenum, which significantly improves its corrosion resistance—especially against chloride ions. This makes 316 more suitable for seawater, chemical, coastal, and other harsh working conditions, with a longer service life and higher operational stability than 304.
Duplex Stainless Steel Pump Body
Leesh Holdings: Professional Top Investment Casting Manufacturers
Leesh Holdings provides top Lost Wax Casting Manufacturer (lost wax casting) for global industrial clients, delivering high-precision, complex metal components with consistent quality, cost efficiency, and reliable lead times.
With years of manufacturing experience and advanced production facilities, we specialize in custom investment casting solutions for aerospace, automotive, medical, machinery, marine, and other high-demand industries.
Leesh Investment Casting Process
Core Advantages of Our Investment Casting Service
✅ One Stop Solution
Full service from tooling manufacturing to finish machining, providing you with total solutions.
✅ Global Service
Professional English-speaking team with at least 5 years of global customer service experience.
✅ Experienced Engineers
Mature engineer training system, knowledgeable, energetic and enthusiastic technical support.
✅ Well-Maintained Equipment
Strict equipment maintenance ensures stable and reliable product quality and consistent performance.
✅ Cost & Production Efficiency
Low rejection rate and optimized process bring the best balance between cost and benefit for global customers.
✅ Professional Inspection & Testing
Complete quality inspection including material, dimension, NDT, scanning and strict testing for every product.
Technical Specifications & Parameters
| Manufacturing Method | OEM Investment Casting Services (Lost Wax Casting) |
| Material Standard | GB, ANSI, BS, DIN, JIS, ASTM, ASME, AISI, etc |
| Main Materials | Carbon steel, Low carbon steel, Middle carbon steel, G35, G45, WCB, WCA, WCC, ISO 340-550, etc. Alloy Carbon steel: G25CrMo4, Heat Resistant Steel, etc. Stainless Steel: SUS 304, 304L, 316, 316L, CF8, CF8M, G-X7CrNiNb1189, AS2074 or according to customer specific requirement. Copper, Brass, Bronze |
| Weight Range | 0.01 kgs to 100 kgs |
| Cast Hole Min. Dia. | Ø2mm |
| General Casting Tolerance | CT4-CT7 |
| Design Software | UG, Pro-E, Inventor |
| Dwg Format | STP, STEP, IGS, STP, X_T, DXF, DWG, Pro/E, PDF, SLDPRT |
| Mould Manufacturing | Yes |
| Casting Simulation | Yes |
| Ultimate machining tolerance | 0.005mm |
| Quality Control | RT, UT, MT, PT, CMM, SCAN, Chemical and Mechanical Property Testing, Spectrometer, etc |
| Finish Roughness | Ra1.6-Ra3.2 according to customer requirement |
| Logo/ID | Silk-screening, Laser Marking, Engrave, Painting |
| Heat Treatment | Normalization, Annealing, Quenching and Tempering, Case Hardening, Nitriding, Carbon Nitriding, Induction Quenching, etc |
| Surface Treatment | Shot/sand blast, Polishing, Surface Passivation, Painting, Anodizing, Powder coating, ED-Coating, Chrome Plating, zinc-plate, Dacromat coating, Finish Painting, hot-dip galvanizing, etc |
Our Investment Casting Services Scope
- Custom investment casting for metal parts (0.01kg – 100kg)
- Precision CNC machining & secondary processing
- Surface treatment: polishing, sandblasting, painting, passivation, plating
- Non-destructive testing (NDT), dimensional inspection & material certification
- Prototype & mass production solutions
Applicable Industries
Automotive
Medical Equipment
Industrial Machinery
Marine & Shipbuilding
Valve & Pump Parts
Construction Hardware
Quality Assurance
Leesh Holdings implements strict quality-every casting part under full inspection to ensure dimensional accuracy, material consistency, and performance stability for your critical applications.
Contact Us for Investment Casting Quote
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