Stainless Steel Investment Casting for Custom Cast Parts


Custom stainless steel cast and CNC machined components for pump and valve systems, food equipment, medical devices, marine hardware, and industrial machinery applications.


Zeren supports stainless steel investment casting based on customer drawings, samples, material requirements, and application conditions. We work with common stainless steel grades such as 304, 316, 316L, 410, and 430, with CNC machining and surface finishing available for critical dimensions and functional surfaces.

Stainless steel investment casting components with CNC machined surfaces

Quick Navigation for Stainless Steel Casting Solutions

Quickly find stainless steel grade options, typical components, industry applications, machining support, finishing methods, quality control, and RFQ guidance for your custom casting project.

Why Stainless Steel Works Well for Investment Casting


Stainless steel is widely used for custom investment cast parts because it combines corrosion resistance, strength, clean surface quality, and good compatibility with secondary machining. For components with complex geometry, sealing surfaces, flow passages, mounting areas, or assembly features, investment casting helps form the near-net shape before CNC machining is applied to critical dimensions.

Corrosion Resistance
Stainless steel is suitable for components exposed to moisture, fluid media, outdoor environments, or mild chemical service conditions.

Clean Surface Quality

The silica sol investment casting process supports smooth casting surfaces, making stainless steel a good option for components requiring clean appearance or hygienic performance.

Complex Geometry

Investment casting is suitable for stainless steel parts with curved surfaces, thin walls, internal profiles, bosses, ribs, and other complex shapes.

CNC Machining Compatibility

Sealing faces, bores, threads, holes, flat mounting surfaces, and assembly datums can be machined after casting for improved dimensional accuracy.

Flexible Grade Selection

Different stainless steel grades can be selected according to corrosion resistance, strength, magnetic properties, machining behavior, and application environment.

Common Stainless Steel Grades for Investment Casting


Different stainless steel grades offer different levels of corrosion resistance, strength, machinability, magnetic behavior, and cost efficiency. The most suitable grade should be selected according to the working environment, fluid medium, mechanical load, surface finish requirement, and post-machining needs.

Stainless Steel Grade Selection Guide
The following table provides a general chemical composition reference for commonly used stainless steel casting grades. Final material selection should be confirmed according to the drawing, standard requirement, and application environment.
GradeMaterial PositioningTypical ApplicationsSelection Notes
304 Stainless SteelGeneral-purpose corrosion-resistant stainless steelValve parts, pump components, food equipment parts, hardware, general industrial partsGood balance of corrosion resistance, formability, and cost
316 Stainless SteelHigher corrosion resistance than 304, especially for more demanding fluid or marine-related environmentsPump and valve parts, marine fittings, chemical-related components, fluid system partsCommon choice when better corrosion resistance is required
316L Stainless SteelLow-carbon version of 316Medical equipment components, food equipment parts, welded or corrosion-sensitive partsSuitable when clean surface quality and corrosion control are important
201 / 202 Stainless SteelMore economical austenitic stainless steel optionsGeneral hardware, structural fittings, non-critical industrial partsCan be considered when cost is important and corrosion requirements are moderate
410 Stainless SteelMartensitic stainless steel with higher strength and hardness potentialMechanical parts, wear-related components, shafts, brackets, industrial fittingsCan be considered when strength or hardness is more important
430 Stainless SteelFerritic stainless steel with moderate corrosion resistanceHardware parts, decorative-functional components, general industrial partsMagnetic stainless steel option with lower nickel content
Chemical Composition Reference for Common Stainless Steel Grades

The chemical composition values below are for general material reference only. Final material requirements should follow customer drawings, purchase specifications, applicable standards, and actual material certificates.

GBAISI/ASTMJISCSiMnPSCrNiNMo
(%)(%)(%)(%)(%)(%)(%)(%)(%)(%)
06Cr19Ni10 / old 0Cr18Ni9304SUS304≤0.08≤1.00≤2.00≤0.045≤0.03018.00–20.008.00–10.50 / 8.00–11.00≤0.10—
06Cr17Ni12Mo2 / old 0Cr17Ni12Mo2316SUS316≤0.08≤1.00≤2.00≤0.045≤0.03016.00–18.0010.00–14.00≤0.102.00–3.00
022Cr17Ni12Mo2 / old 00Cr17Ni14Mo2316LSUS316L≤0.030≤1.00≤2.00≤0.045≤0.03016.00–18.0010.00–14.00≤0.102.00–3.00
1Cr17Mn6Ni5N201SUS201≤0.15≤1.005.50–7.50≤0.060≤0.03016.00–18.003.50–5.50≤0.25—
1Cr18Mn8Ni5N202SUS202≤0.15≤1.007.50–10.00≤0.060≤0.03017.00–19.004.00–6.00≤0.25—
12Cr13 / old 1Cr13410SUS410≤0.15≤1.00≤1.00≤0.040≤0.03011.50–13.50≤0.75——
10Cr17 / old 1Cr17430SUS430≤0.12≤1.00≤1.00≤0.040≤0.03016.00–18.00≤0.75——
Common Wrought and Cast Stainless Steel Grade References
Common NameCast Grade ReferenceTypical Use
304 Stainless SteelCF8General corrosion-resistant cast parts
316 Stainless SteelCF8MPump, valve, marine and chemical-related parts
316L Stainless SteelCF3MLow-carbon, corrosion-sensitive or clean-surface applications
410 Stainless SteelCA15 / similar martensitic casting gradesStrength or hardness-focused components

Typical Stainless Steel Components We Produce


We manufacture custom stainless steel investment castings for industrial OEM projects, with support for CNC machining, surface finishing, and inspection based on customer drawings or samples.

Stainless steel valve body casting with machined sealing surfaces
Valve Bodies
Custom stainless steel valve body castings for fluid control systems requiring corrosion resistance, dimensional consistency, and precision-machined sealing and connection surfaces.
Stainless steel pump component casting with precision machined surfaces
Pump Components

Stainless steel pump components such as housings, covers, and related cast parts designed for demanding applications that require strength, reliability, and accurate machined features.

Stainless steel pipe fitting casting for industrial fluid connections
Pipe Fittings & Connectors

Investment cast stainless steel pipe fittings and connectors for fluid transfer systems, offering reliable corrosion resistance, durable service performance, and precise connection geometry.

Stainless steel marine hardware casting with corrosion resistant finish
Marine Hardware

Stainless steel marine hardware components produced for corrosive outdoor and marine environments where long-term durability, strength, and clean surface quality are important.

Stainless steel machinery part casting with CNC machined features
Machinery Parts

Custom stainless steel machinery parts for industrial equipment applications that require complex shapes, stable quality, and precision machining on functional surfaces.

Stainless steel equipment component casting for clean industrial applications
Food & Medical Equipment Parts

Stainless steel components for food processing and medical equipment applications where clean surface finish, corrosion resistance, and precise manufacturing are essential.

Stainless Steel Casting Applications Across Industries


Stainless steel investment castings are used across many industrial applications where corrosion resistance, clean surface quality, dimensional consistency, and reliable mechanical performance are important.

Pump & Valve
Valve bodies, pump housings, impellers, reducing elbows, connector seats, and other fluid control components.
Petrochemical & Marine
Corrosion-resistant components for chemical fluid systems, marine fittings, offshore equipment, pump parts, and valve components.
Industrial Machinery
Custom machinery parts, brackets, housings, connector blocks, and stainless steel structural components for equipment assemblies.
Food Processing Equipment
Clean-surface stainless steel components for food processing, handling, and equipment assembly applications.
Medical Equipment
Precision stainless steel cast and machined components for medical equipment support structures, mounting parts, and functional assemblies.

Investment Casting and CNC Machining for Stainless Steel Parts


Many stainless steel components require both near-net-shape casting and post-casting machining. Investment casting forms the main structure, while CNC machining is used for critical dimensions, sealing faces, threaded holes, bores, flat surfaces, and assembly areas.

Stainless steel casting components with CNC machined surfaces

1. Drawing or Sample Review

We review the part structure, material requirement, tolerance areas, surface finish needs, and application conditions before quoting.

2. Tooling and Wax Pattern Production

Tooling is prepared according to the confirmed design, and wax patterns are produced for the investment casting process.
3. Stainless Steel Investment Casting
The silica sol investment casting process is used to produce stainless steel components with complex geometry and good surface quality.
4. CNC Machining and Inspection
Critical surfaces and dimensions are machined after casting, followed by dimensional inspection and material verification when required.
This combined process helps reduce excessive machining from solid material while still allowing critical surfaces and assembly features to meet drawing requirements.
Surface Finishing Options for Stainless Steel Castings

Surface finishing can be selected according to appearance, corrosion resistance, cleaning requirements, assembly needs, and end-use conditions. For stainless steel castings, both functional and cosmetic surface treatments can be evaluated based on the part design.

FinishSuitable For
Shot blastingGeneral matte surface and removal of casting residue
Sand blastingUniform surface texture and pre-treatment
PolishingImproved appearance and smoother surface
Mirror polishingDecorative or clean-surface applications
PassivationImproved surface corrosion resistance for stainless steel parts
ElectropolishingHigher cleanliness and smoother surface for selected applications
Available finishing options depend on part geometry, material grade, surface requirements, and production quantity.
Typical Finishing Combinations for Stainless Steel Castings
RequirementSuggested Finishing Option
General industrial appearanceShot blasting or sand blasting
Better corrosion resistancePassivation after cleaning
Decorative surfacePolishing or mirror polishing
Clean surface for food or medical equipmentFine polishing, passivation or electropolishing
Machined sealing surfacesCNC machining + local polishing if required
Quality Control for Stainless Steel Investment Castings

For stainless steel casting projects, quality control should cover material verification, casting appearance, dimensional accuracy, machined surfaces, and application-specific requirements. Zeren can support inspection based on customer drawings, samples, and project requirements.

Quality inspection for stainless steel investment casting parts
1. Material Verification
Chemical composition inspection can be arranged to confirm stainless steel grade requirements.
2. Dimensional Inspection
Key dimensions, machined surfaces, bores, holes, and assembly interfaces can be checked according to drawings.
3. Surface Appearance Check
Casting surface, polishing quality, visible defects, and finishing consistency can be reviewed before shipment.
4. Machining Accuracy Control
Critical CNC-machined areas such as sealing faces, threads, and mounting surfaces are checked according to tolerance requirements.
5. Sample Approval Before Batch Production
For new custom projects, samples can be produced and confirmed before full batch production.
Inspection Reports Available Upon Request
Chemical composition report
Dimensional inspection report
Surface appearance photos
Machining inspection records
Material certificate if available or required by project

Explore Related Casting Solutions


Compare alternative casting materials and supporting manufacturing capabilities to find the right solution for your custom part.

Alternative Materials
Duplex Stainless Steel
For more demanding corrosive environments involving chlorides, seawater, or marine-related service conditions, duplex stainless steel may be considered.

Explore Duplex Stainless Steel

Carbon Steel
For structural or cost-sensitive parts where corrosion resistance is not the main requirement, carbon steel may be a practical material option.

Explore Carbon Steel

Alloy Steel
For components requiring higher strength, toughness, wear resistance, or mechanical load capacity, alloy steel may be more suitable than stainless steel.

Explore Alloy Steel

Supporting Capabilities
Investment Casting
For complex stainless steel geometries, near-net-shape production, smooth casting surfaces, and repeatable casting quality.
CNC Machining
For sealing faces, bores, threads, flat mounting surfaces, and other critical dimensions after stainless steel casting.
Surface Finishing
For polishing, blasting, passivation, and other finishing requirements based on appearance, corrosion resistance, or functional needs.
Quality Control
For dimensional inspection, material verification, surface checks, and project-specific quality control documentation.
Frequently Asked Questions About Stainless Steel Investment Casting
Q1. What stainless steel grades can be used for investment casting?


Common stainless steel grades include 304, 316, 316L, 410, 430, 201, and 202. The suitable grade depends on corrosion resistance, strength, magnetic behavior, machining needs, and application environment.
Q2. What is the difference between 304 and 316 stainless steel castings?


304 stainless steel is a common general-purpose grade with good corrosion resistance and wide application flexibility. 316 stainless steel provides better corrosion resistance for more demanding fluid, marine, or chemical-related environments.
Q3. When should 316L stainless steel be considered?


316L can be considered when lower carbon content, clean surface quality, welding-related requirements, or corrosion-sensitive applications are important.
Q4. Can stainless steel castings be CNC machined after casting?


Yes. Stainless steel investment castings are often CNC machined after casting for sealing faces, bores, holes, threads, flat mounting areas, and other critical dimensions.
Q5. Is stainless steel investment casting suitable for pump and valve parts?


Yes. Stainless steel is widely used for pump and valve components such as valve bodies, pump housings, impellers, reducing elbows, connector seats, and fittings where corrosion resistance and machined sealing surfaces are important.
Q6. What information is needed for a stainless steel casting quotation?


A drawing, 3D file, sample photo, material grade, quantity, tolerance requirement, surface finish requirement, and application environment will help us evaluate the most suitable casting and machining solution.


Need Support for a Stainless Steel Casting Project?

Send us your drawing, sample, material requirement, or application details, and our team will help evaluate a suitable stainless steel investment casting and CNC machining solution for your custom component project.
Engineering support for custom stainless steel casting projects