High grade steel components by using investment casting

CIREX is one of the largest steel-casting companies in the world and produces complex castings with extreme precision using the “lost-wax” method. Thanks to this versatile method our engineers have considerable freedom in the product design and choice of materials. This means that in consultation with you we can produce optimum castings that meet your exact wishes and requirements.


How does ‘investment casting‘ (lost-wax) work? Click on “read more” for an overview of the steps and phases involved. CIREX is one of the largest lost-wax foundries in the world. Using this method, we produce high-quality investment castings of complex shapes with extreme precision. As this process offers considerable freedom in the casting design and material choice, we can produce the castings according to your specific requirements with maximum efficiency.

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CIREX produces precision castings using the lost-wax technique. These castings have low surface roughness values, precise tolerances and are the highest quality steel castings available on the market. They are often used for components that operate in hostile environments, such as large differences in temperature or where the components are required to be especially hard, strong or light. To meet these tough demands, special alloys are often used for these castings.


Shape tolerance:
Dimensional tolerances:


Freedom in style and design
High surface quality & low roughness values (Ra 1.6 – 6.3 µm)
High dimensional accuracy and precise tolerances (VDG P690 D1)
Virtually any steel alloy can be cast
Complex shapes can be cast as a single component
Little to no machining is required
Products with undercuts can be cast
Suitable for smaller and larger series


CIREX’s activities are spread across three locations. Besides the headquarters and knowledge centre in the Netherlands (Almelo), there are two locations in the Czech Republic (Koprivnice). Cirex employs about 280 people.


At the knowledge centre and headquarters in Almelo, a team of specialist engineers, product developers, metallurgists …

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CIREX Foundry CZ

For the production of smaller series of complex steel components, CIREX has set up a modern lost- wax model foundry in the Czech Republic. Here, CIREX can produce cast pieces of …

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CIREX Finishing & Machining

cirex finishing machining investement casting

The cast components from the foundries in the Netherlands and the Czech Republic are finished at this location according to the customer-specific product specifications …

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cirex investment castings properties


If you select CIREX to have your steel component developed and produced, then you are opting for quality, certainty and reliability. From idea to implementation. Our investment casting process has the following characteristics:

  • Significant freedom of shape and design
  • Nearly every steel alloy is possible
  • High degree of dimensioning precision
  • No release angle required
  • High surface quality
  • Obviates mechanical post-processing
  • Non-releasing cores can be cast
cirex investment casting tolerances


Precise dimensioning characterises the lost-wax method. Extremely precise tolerances often make a design needlessly expensive. With our decades of knowledge and experience we can save you costs by determining the best dimensioning in consultation with you. The final result? Optimal use of our casting process.

The tolerances for “lost wax model” castings are established in an international norm: VDG P690. CIREX produces according to this norm, such that class D1 is considered the standard.

  • Class D1: Standard tolerances
  • Class D2: Precise tolerances
  • Class D3: Extremely precise tolerances, feasible for a limited number of dimensions and/or surfaces.

The production process at CIREX is highly automated. This results in decreased process spread. Because of our human-independent production, the casting process is extremely consistent. This allows CIREX to produce cast pieces more precisely than international standards require.

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surface quality investment castings


The roughness of CIREX precision castings varies from Ra 1.6 tot 6.3 µm, depending on the steel alloy used. This low roughness means that an additional processing is often not needed. That can result in considerable cost savings for you. However, if lower roughness values still are required then an extra surface treatment may be necessary, such as electrolytic polishing …

Investment casting materials

At CIREX, we always start with the product’s functionality. Once the functionality is clear, the product is developed further. An essential part of this is the choice of material. A good design depends entirely on the proper choice of material. It’s important to know the properties that the steel must possess. Consider, for example:

  • Mechanical properties      (hardness, tensile strength, elongation and elasticity)
  • Thermal properties            (heat resistance)
  • Chemical properties          (acid resistance and the ability to withstand corrosion)

Metallurgical specialists at CIREX will be glad to help you choose the optimum alloy for your application. Also when it comes to choosing the right chemical composition, structure, hardness, tensile strength or heat resistance.

Investment casting surface-hardened steels

Structural components with high levels of abrasion resistance combined with a tough core. Products that are subject to conditions requiring both abrasion resistance and toughness.

CX no.Mat. no.SymbolSimilar toHeat treatmentProof stress Rp0,2Tensile strength (N/mm²)Elongation (%)Hardness
151.0401C15 / GS38SAE M1015Surface hardening≥ 430700-900≈ 12≥ 700 HV
9021.586014NiCr18-Surface hardening≥ 835900-1200≈ 10-
161.5919G15CrNi6SAE 3115Surface hardening≥ 6801000-1300≈ 8≥ 700 HV
9361.701515Cr3-Surface hardening≥ 440690-880≈ 11-
171.7131G16MnCr5SAE 5115Surface hardening≥ 600900-1200≈ 10≥ 700 HV
9141.732120MoCr4AISI 4118 / 4120 / 4121Surface hardening----
1.7242G16CrMo4-Surface hardening-600-800-≥ 680 HV1.7242

Hardenable and nitrided steel

Nitrided steel for components with a high abrasion resistance combined with a high tensile strength.

CX no.Mat. no.SymbolSimilar toHeat treatmentProof stress Rp0,2Tensile strength (N/mm2)Elongation (%)Hardness
101.0503C45GS 60Refining≥ 500700-85015-25 HRc
9351.5028C30-Refining≥ 400600-750≥ 15-
9511.6220G20Mn5-Refining≥ 300500-650≥ 22-
121.658234CrNiMo6-Refining≥ 450-1150600-1350≥ 6-1222-55 HRc
9371.703437Cr4-Refining≥ 650-950750-1200≥ 3-1218-35 HRc
91.721825CrMo4-Refining≥ 600750-900≥ 10-
9101.722034CrMo4-Refining≥ 550-800700-1050≥ 6-1025-40 HRc
111.7225GS-42CrMo4AISI 4140Refining≥ 650-1250800-1350≥ 4-1022-58 HRc
111.7231G42CrMo4AISI 4140Refining≥ 650-1250800-1350≥ 4-1022-58 HRc
411.8160G51CrV4SEW 835Refining≥ 8501100-1250≥ 634-58 HRc

Tooling steel

A steel alloy characterised by a high degree of abrasion resistance and toughness. Therefore suitable for tools that must endure heavy loads.

CX no.Mat. Nr.SymbolSimilair toHeat treatmentFeCSiMn
191.2346GX38CrMoV5-1AISI H11Hardeningrest0,36-0,420,90-1,200,30-0,50
9251.2361X91CrMoV18-Hardeningrest0,85-0,95< 1,0< 1,0
451.2436X210CrW12AISI D6Hardeningrest2,00-2,250,10-0,400,15-0,45
9501.3505100Cr6-Soft annealingrest0,95-1,050,15-0,300,25-0,40

Stainless steel

An alloy characterised by a high degree of corrosion-resistance and toughness. Stainless steel is often used in corrosive environments.

CX no.Mat. no.SymbolSimilar toHeat treatmentProof stress Rp0,2Tensile strength (N/mm²)Elongation (%)Hardness
9471.4008GX7CrNiMo12-1AISI 410Refining≥ 440590-790≈ 15≥ 90 HRb
71.4027GX20Cr14-Refining≥ 400590-790≈ 1518-50 HRc
9571.4036GX46Cr13-Refining-750-900-15-53 HRc
221.4059GX22CrNi17-Refining600- 750800-950≈ 822-50 HRc
9411.4162X2CrMnNiN21-5-1LDX 2101®Solution annealing + quench hardening----
251.4308GX5CrNi19-10AISI 304 / CF8Solution annealing + quench hardening> 175> 440> 3075-90 HRb
341.4309GX2CrNi19-11AISI 304L / CF3Casting condition> 210440-460> 3070-80 HRb
241.4317GX4CrNi13-4-Refining> 650800-1000> 1522-30 HRc
271.4408GX5CrNiMi19-11-2AISI 316 / CF8MSolution annealing + quench hardening> 200> 450> 2075-90 HRb
281.4409GX2CrNiMi19-11-2AISI 316L / CF3MSolution annealing + quench hardening> 200> 450> 2075-90 HRb
9451.4468GX2CrNiMoN25-6-3-Casting condition> 650> 22> 92 HRb
9551.4470GX2CrNiMoN22-5-3-Normal annealing> 450680-880> 30> 93 HRb
261.4827GX8CrNiNb19-10-Solution annealing + quench hardening> 175> 440> 2075-95 HRb