Benefits of Stainless Steel Investment Casting
- Exceptional Corrosion Resistance
- Stable Performance under Extreme Temperatures
- Excellent Dimensional Tolerances and Surface Finish
- Extremely Wide Range of Castable Weights (0.022 pounds to 220 pounds)
- Complex Geometric Casting Capacity
- Consistently High Quality in Batch Production
Stainless Steel Grade We Can Cast
Pingheng Machinery offers a variety of stainless steel material options for your stainless steel casting projects.
- 304: The most commonly used general-purpose stainless steel.
- 304L: A low-carbon variant of 304 with improved resistance to intergranular corrosion.
- 316: Contains added molybdenum for enhanced resistance to chloride corrosion.
- 316L: A low-carbon variant of 316 offering superior corrosion resistance after welding.
- 17-4PH: A Higher strength can be achieved through heat treatment.
What is Stainless Steel Investment Casting
Stainless steel investment casting is poured through investment casting, which is also called lost wax casting. As one of the most commonly used materials in investment casting, stainless steel is known for its exceptional corrosion resistance, high strength and excellent surface finish.
In addition to a chromium content exceeding 10.5%, stainless steel also incorporates elements such as nickel and molybdenum to enhance its corrosion resistance and high-temperature performance. If your casting requires better performance in a harsh environment, such as extreme temperatures or a high-chlorine environment, stainless steel casting is a better choice.
Casting of stainless steel is widely applied in industries with a demanding work environment, such as pump& valve, petrochemical, automotive, food processing, medical, industrial machinery, and so on.
Pinghen Machinery can customise your stainless steel casting projects to meet your various requirements. We can pour stainless steel alloys, including 316(L), 304(L), and 17-4 PH stainless steel. Feel free to contact us if you’re interested!
Outstanding Corrosion Resistance of Stainless Steel Investment Casting
Corrosion resistance is the most prominent feature of stainless steel castings. During the casting production process, Pingheng Machinery subjects them to a series of treatments, including solution annealing, acid pickling, and passivation to enhance the corrosion resistance of stainless steel castings. We possess salt spray testing equipment capable of ensuring stainless steel castings remain rust-free during standard salt spray tests lasting 72 to 720
hours, meeting your diverse corrosion resistance requirements for castings.
Stainless Steel Investment Casting Tolerances We Achieve
Pingheng Machinery’s stainless steel investment castings can achieve dimensional tolerances between CT6 -CT8. For smaller stainless steel castings or localised areas within castings, we can accomplish a CT4 tolerance grade. This requires specific analysis based on your drawings.
Additionally, we are capable of casting components with wall thicknesses ranging from 2.5 to 3 mm and maintaining linear tolerances within ±0.01mm.
Strict Quality Control of Your Stainless Steel Casting in Pingheng Machinery
Pingheng Machinery obtained IATF 16949 certification.
With comprehensive testing equipment (HEXAGON Coordinate Measuring Machine, SPECTRO Spectrometer, Air Tightness Testing Equipment, Salt Spray Test Equipment, Dynamic Balance Testing Equipment, and Hardness Testing Machine）and a 20-member professional quality team, we can monitor your stainless steel casting projects throughout the entire process to ensure casting quality. Before shipment, Pingheng Machinery can also provide chemical composition reports, full dimensional reports, heat treatment reports, and mechanical property reports for each batch of your stainless steel castings.
Investment Casting Secondary & Support Services We Offer
- Machining (CNC Machining, Milling, Drilling, Tapping)
- Surface & Finishing Treatments （Pickling, Passivation, Sandblasting, Polishing）
- Heat Treatment (Solution Treatment, Ageing Treatment）
- Hardness Treatment
- Welding
- Rapid Prototyping (3D Prototyping Service)
- Product Assembly Service
Why Choose Pingheng Machinery for Your Stainless Steel Casting Project
At Pingheng, our experienced technical team can provide professional assessments and effective recommendations for your casting projects promptly. Our one-stop custom casting service ensures rigorous quality control at every stage—from mould development, casting, machining, and inspection to final shipment. Throughout the project, we continuously optimise production processes to minimise issues such as porosity, gas holes, and sand inclusions. We not only guarantee precision in machined areas but also ensure your castings meet technical specifications as per drawings, maintaining consistent and stable quality across every order.
We are committed to providing you with high-quality, cost-effective custom stainless steel castings!
Wide Application of Stainless Steel Investment Casting
Stainless steel castings produced by Pingheng Machinery have been applied across multiple industries, including petrochemical, automotive, pumps, valves, marine, medical, food processing, file protection, pipe fitting, and more.
wellhead safety valves, booster pumps, and transfer pumps for pipelines, as well as impellers and turbines of the oil and gas industry.
Bushings, actuator shafts, connecting rods, turbine housings, and EGR valves in automotive components.
Pump body, fittings, bracket, handle, impeller (axial flow impeller, radial flow impeller, and mixed-flow impeller), shaft sleeve, and volute casing.
stainless steel valve casting： Wedge gate valves, flat gate valves, ball valves, globe valves, plug valves, butterfly valves, stop valves, foot valves, shut-off valves, and check valves, etc.
More About Stainless Steel Casting
- Data Sheet
- Gallery
| Stainless Steel Grades | Tensile Strength （MPa） | Yield Strength （MPa） | Elongation % | Hardness (HV) |
| 304 Stainless Steel | ≥485 | ≥205 | ≥40 | ≤200 |
| 316 Stainless Steel | ≥515 | ≥205 | ≥40 | ≤150 |
| 304L Stainless Steel | ≥515 | ≥205 | ≥40 | ≤210 |
| 316L Stainless Steel | ≥485 | ≥170 | ≥40 | ≤150 |
| 17-4 PH Stainless Steel | ≥1100 | ≥1000 | ≥10% | ≤445 |
Related Product
Automotive Parts CastingsStainless steel casting parts for automotive engine exhaust emission control(EGR).
Pipe Fitting CastingStainless steel pipe castings for water treatment equipment.
Industrial Equipment CastingStainless steel investment castings for industrial slurry mixing equipment
Bracket CastingMirror-polished stainless steel castings for industrial equipment brackets
Precision investment casting process enables us to produce stainless steel casting parts with strict tolerances, complex geometric shapes, and smooth surfaces.
There are various stainless steel casting alloys. Common stainless steel grades used in investment casting include austenitic stainless steels (such as 304 and 316), martensitic stainless steels (such as 410 and 440C), and precipitation-hardening (PH) stainless steels (such as 17-4 PH).
Austenitic stainless steels are widely favoured primarily for their excellent corrosion resistance, while martensitic and precipitation-hardening stainless steels are highly valued for their ability to achieve high strength and hardness through heat treatment.
The investment casting stainless steel process includes the following steps.
Mould Making: A steel or aluminium mould is fabricated based on the 3D drawings of the target stainless steel casting.
Wax Injection: Wax is poured into the mould and allowed to cool, forming a wax pattern. This entire process must be conducted in a temperature-controlled environment. Water-soluble cores or ceramic cores can be selected if required.
Wax Trimming and Assembly: After minor trimming, the wax pattern is assembled onto a pouring system to form a wax tree, enabling single-pour casting.
Shell Building: The wax tree is immersed in ceramic slurry, followed immediately by sprinkling coarse sand particles onto its surface. This process is repeated after each layer of slurry fully dries until the ceramic shell on the wax pattern surface reaches the desired thickness.
Dewaxing: Once the ceramic shell is fully solidified, it is placed in an autoclave to melt the wax for recycling and preheat the pattern for casting.
Pouring: Molten stainless steel is poured into the cavity until it fills the mould cavity.
Shell Removal: After the internal metal has fully cooled, the shell is removed by vibration to obtain the stainless steel investment casting. The entire casting tree is then suspended and tumbled.
Cutting and Grinding: The casting is cut from the casting tree and undergoes shot blasting and grinding to remove excess gates.
Finishing: Finishing processes are performed according to the requirements of the target stainless steel casting.
We all know that the cost of stainless steel investment casting is not low. What factors influence the expense of stainless steel investment casting? Here are several key aspects.
Casting Material Cost
This refers to the selection of stainless steel casting grades, as different grades carry varying costs. Generally, higher-grade stainless steel casting grades command higher prices.
Production Volume
This refers to the order quantity. Initial tooling costs for investment casting are substantial, making it less economical for tiny batches of stainless steel castings. However, unit costs decrease as the number of castings increases.
Number of Shell Layers
Due to varying designs and structures among stainless steel castings, more complex castings require additional shell layers during shell formation, thereby increasing costs.
Machining
The number of machined surfaces required, the machining precision to be achieved, and the difficulty of machining the casting will vary depending on the desired shape of your target casting. These factors collectively influence the final casting cost.
Other Expenses
Additional costs include expenses incurred for finishing, post-processing, heat treatment, packaging, and other steps performed according to customer specifications.
Due to the complex nature of stainless steel casting processes, improper operation at any stage may result in casting defects. Some defects can be repaired after casting, while others must be minimised during the casting process. The following are common defects in stainless steel investment castings.
1) Porosity
Porosities are circular or oval-shaped cavities with smooth walls that may appear inside or on the surface of castings. They are among the most prevalent casting defects in industry and significantly reduce material strength.
Causes: High gas content in molten metal during melting; improper pouring system design; insufficient shell preheating or poor permeability.
Solutions: Degas molten metal before pouring.
Control pouring speed during casting.
Select appropriate shell materials to minimise gas entrapment.
2) Shrinkage Defects (Shrink Cavity, Shrinkage Porosity)
Shrinkage defects encompass shrinkage porosity and shrinkage cavity. Shrinkage porosity refers to jagged or linear defects appearing on the casting surface when volume contraction during metal melt cooling is not promptly compensated by incoming material. Shrinkage cavity denotes large, concentrated, irregular cavities forming in the last-solidified regions of the casting.
Causes: Inconsistent cooling rates due to improper mould design or pouring; uneven casting wall thickness.
Solutions: Design a rational gating system to ensure uniform cooling.
Select appropriate mould materials to guarantee even cooling.
3) Cracks (Hot Tears)
Cracks occur when metal is constrained by the mould during cooling and contraction (preventing full shrinkage). They typically appear linear or curved.
Causes: Uneven casting wall thickness and inconsistent cooling rates; insufficient mould thermal stress resistance.
Solutions: Control casting thickness.
Design moulds to minimise thermal stress.
Regulate cooling and solidification rates.
4) Cold Shut
Cold shut refers to discontinuities or weak areas forming in castings when two molten metal streams fail to fully merge before solidifying.
Causes: Insufficient molten metal temperature; improper pouring system design; inadequate metal fluidity.
Solutions: Adjust pouring temperature.
Optimise the pouring system.
Add metal to enhance pouring fluidity.
5) Inclusions
Inclusions refer to non-metallic impurities present within metal castings. These relatively regular-shaped defects compromise the structural integrity of the casting.
Causes: Inadequate metal purification; improper pouring process; lack of a filtration system.
Solutions: Select high-quality raw materials.
Ensure proper environmental control during the pouring process.
Consider removing impurities through a wax filtration system.
6) Surface Defects
Surface defects in castings refer to visible imperfections such as roughness, cracks, or pits.
Causes: Damaged/poor surface finish moulds; moisture or gas trapped inside moulds; unstable pouring temperature.
Solutions: Ensure moulds are intact and meet specifications.
Ensure no moisture or gas remains inside moulds.
Control pouring temperature and metal cooling rate.
Yes, stainless steel investment castings can certainly undergo heat treatment. Through processes such as solution treatment, precipitation hardening, and ageing treatment, stainless steel investment castings can achieve superior mechanical properties, enhanced corrosion resistance, or specific performance improvements.
Yes, SS investment casting offers a variety of surface treatments. These include shot peening, sandblasting, acid pickling and passivation, electropolishing, vibratory finishing, brushed finishes, mirror polishing, PVD coatings, and satin finishing.
Within the stainless steel family, 304 and 316 stainless steel are frequently compared. They exhibit significant differences in physical, chemical, mechanical, and processing properties. If you’re interested in their similarities and differences, click “304 vs 316 Stainless Steel – the Ultimate Guide for Beginners and Experts”.
17-4 PH stainless steel castings combine high strength, high hardness, and excellent corrosion resistance. Additionally, they can achieve even greater strength through heat treatment. If your casting requirements encompass these properties, then 17-4 PH stainless steel castings are the ideal choice for you.
As is well known, 316 stainless steel castings offer outstanding corrosion resistance. Compared to them, 316L castings not only provide superior corrosion resistance but also feature excellent weldability and machinability. Therefore, if your project demands high corrosion resistance and weldability from castings, 316L stainless steel castings are a reliable choice.
304 is hailed as the all-rounder of the stainless steel world. It strikes an excellent balance between corrosion resistance, strength, and other properties at a more economical price point. Therefore, if your castings are used in a relatively mild environment without special requirements, the cost-effective 304 stainless steel investment castings will be your best choice.
Yes. You may be surprised that stainless steel casting can also rust, but don’t worry—it doesn’t happen easily. Possible causes of rusting:
Long-term impact and abrasion from hard objects may damage the surface oxide layer.
Corrosion by strong chlorides.
Electrochemical reactions with other metals.
Improper welding reduces chromium content within the material.
How to prevent stainless steel rusting:
Optimise casting design to avoid gaps and dead corners.
Perform regular maintenance.
Store properly.
Strictly adhere to welding and fastening specifications.
Select more corrosion-resistant stainless steel grades.
If you want to know more about the rust of stainless steel casting, click “Why does Stainless Steel Rust?”
Although stainless steel exhibits outstanding corrosion resistance, its daily maintenance remains essential.
If stainless steel castings are not exposed to significant contaminants, humid environments, or corrosive media during operation, perform maintenance at least once every six months. This involves rinsing surface dust or debris with water, wiping the surface with a specialised stainless steel cleaner, and ensuring the casting surface is thoroughly dried after a final rinse.
If stainless steel castings operate in extremely harsh conditions, daily, weekly, or monthly inspections and cleaning may be required. Maintenance methods include more frequent cleaning, mechanical washing, and professional passivation treatments. Finally, regularly inspect the operational status of the castings and record the date of each maintenance session for tracking and optimisation purposes.
Finding the right stainless steel investment casting companies for your castings is a crucial step in your casting project. This directly determines whether your project can proceed smoothly. Below are several criteria for evaluating whether a stainless steel casting supplier is a suitable partner, for your reference.
Casting Experience
In the field of investment casting, a stainless steel investment casting manufacturer’s casting experience directly determines its ability to handle unexpected situations and tackle complex projects.
Evaluate Their Technical and Casting Expertise
A company’s technical support forms the core of its capabilities. When assessing whether a stainless steel casting supplier can fulfil your casting project, consider the following three aspects:
Casting Methods: Select the casting process suitable for your project, such as investment casting, sand casting, die casting, etc.
Material Selection: Opt for a foundry capable of casting your project’s specified material or one offering diverse material options.
Value-Added Services: Verify whether the foundry provides required services like heat treatment, non-destructive testing, and thermal testing.
A Comprehensive Quality Control System
Choosing an investment casting company with a comprehensive quality control system directly impacts the quality of your product. This is crucial when selecting a high-quality investment casting stainless steel company.
Company Certification
A company’s quality or technical certifications reflect its overall capabilities and expertise.
Analysing Customer Reviews
Effective communication is an indispensable part of completing your stainless steel casting project. Reputable stainless steel investment casting companies should respond promptly to customer requests and provide ongoing updates on project progress. Reviewing a foundry’s customer feedback offers valuable insight into its performance throughout the project lifecycle.
Balance Price, Quality, and Service
Ultimately, choose the most suitable investment casting stainless steel company by comprehensively evaluating its pricing, product quality, and foundry services.
