Cast iron might be best known as a material for making gates and fences, but it's also still used for many car parts like engine blocks, camshafts, and control arms. If you're manufacturing custom or generic car parts from cast iron for its superior strength and damage resistance, you may be able to make your products even better with a little heat treating. These five benefits are all easily achieved with the help of thermal processing experts.
Improved Wear Resistance
Wear resistance is one of the hottest marketing points when it comes to automobile parts. Cast iron is already very resistant to wear and tear from grinding and abrasion, but heat treating to strengthen the metal increases this characteristic even further. This is because most of the strength added to a piece of cast iron during heat treating affects the surface of the part. Even basic heating and quenching makes the surface tougher as the carbon particles arrange in a more stable matrix.
Is your team struggling to produce a steady supply of products because of uneven machining results? These problems are due to the fact that newly cast pieces of iron vary greatly in mechanical characteristics throughout the part, especially when your design calls for drastic changes in thickness from one end to the other. The slower release of heat in thick sections cause that metal to harden more, creating problems when machining. Heat treating causes the thickest section to machine just as easily as the thin areas. Other improvements in machining from heat treatment include:
- Tighter tolerances, which is essential in many engine parts
- Less deformation and warping during and after machining
- Reduced chances of cracking during bending and cutting.
In addition to evening out the mechanical characteristics of the cast iron parts for better machining, heat treating creates consistency across your product line to reduce complaints and returns from your customers. Cast iron is famous for varying greatly, despite being manufactured from the same exact batch of raw materials and in the same way. Annealing, quenching, and tempering all affect the metal on the particle level to convert carbon and graphite into harder and more closely linked forms like austenite and pearlite. By heat treating every part the same way, you can ensure that all your products offer similar characteristics instead so you're not having to destructively test every batch to catch inferior products.
Faster Stress Relief
Cast iron often develops tiny stresses deep inside the metal as it cools, and those stresses reduce the strength of the parts. While letting parts rest for months on end is a free and reliable way to relieve those stresses before the parts go to your customers, that's a long delay to tie up your supply flow when there's a big demand for immediate shipping. Heat treatment relieves those stresses to stabilize the strength of each component without a two to six month waiting period. This also saves you money if you consider the costs of extra storage space just for parts sitting around.
Increased Resistance to Corrosion
Finally, heat treating is the fastest and most reliable way to keep the cast iron parts from rusting away as they're exposed to chemicals and moisture. Instead of using coatings that wear away with constant vibrations while the vehicle's moving, heat treating increases the corrosion resistance of the metal from the inside out. This means that every worn surface is just as resistant to rust and pitting over the lifetime of the part.
If you want to truly stand out from your competitors in the car parts industry, heat treating is a quick way to do it. The improved fit and toughness of each engine or suspension component you sell will quickly win your company a dedicated customer base.