Custom Invar Parts Manufacturing

Invar is expensive due to its high nickel content (36-48%), which is a costly alloying element. Additionally, the specialized manufacturing processes required to achieve ultra-low thermal expansion coefficients, along with the need for precise composition control and quality assurance testing, contribute to the higher cost compared to standard steels.

Invar typically costs 3-5 times more than standard stainless steel, with prices ranging from $15-30 per pound depending on the specific grade and form. Super Invar can cost 5-8 times more due to its cobalt content and more stringent manufacturing requirements. The exact cost depends on quantity, specifications, and current market conditions.

Invar can be challenging to machine due to its work-hardening characteristics and tendency to generate heat during cutting. However, with proper tool selection, cutting parameters, and coolant application, it can be machined successfully. We use specialized cutting tools and optimized machining strategies to achieve excellent surface finishes and dimensional accuracy.

Standard Invar 36 has a thermal expansion coefficient of about 1.2×10⁻⁶/°C, while Super Invar has an ultra-low coefficient of approximately 0.3×10⁻⁶/°C. Super Invar contains cobalt (5%) in addition to nickel (32%) and iron (63%), making it more expensive but providing superior dimensional stability for the most critical applications like space telescopes and ultra-precision optics.

Invar's main disadvantages include high cost due to nickel content, work-hardening during machining, lower strength compared to some steels, and sensitivity to magnetic fields. It also requires careful handling to avoid work-hardening and may need stress-relieving treatments after machining to maintain dimensional stability.