Is Inconel more expensive than titanium?
Every material used in motorcycle exhaust is consistent with its natural properties and scientific suitability. Titanium, stainless steel and Inconel are high-specification materials with unique properties that make them suitable for use based on chemical stability, toughness, weight and heat resistance.
Here we will explain the main characteristics, uses and production methods of these different materials so that the differences between stainless steel, titanium and Inconel are apparent.
titanium
Known for its high strength-to-weight ratio, this metal element is highly functional for low-weight applications such as racing. Titanium is half the weight of steel but equivalent in strength. Titanium is more expensive than steel and aluminum, but cheaper than Inconel.
At room temperature, there is no reaction between titanium, moisture and oxygen. Titanium and Inconel are similar in terms of material protection in that they form a protective, passivating oxidized surface layer on the material. This is why titanium has strong corrosion resistance. Even in the face of hydrochloric acid and sulfuric acid, titanium can resist!
Additionally, titanium cools quickly, so when used in motorcycle parts like exhausts, it won't deform under such high heat.
There are pure commercial titanium and titanium alloys on the market. The most standard titanium alloy manufactured using vanadium and aluminum is Ti 6AI-4V. This accounts for half of global titanium alloy applications. These versions have greater strength and toughness than pure titanium and are easier to machine. Commercially pure titanium, while highly resistant to corrosion, is more flexible and plastic than its alloy counterparts.
Processed titanium
Titanium alloys also undergo complex hardening processes, making them difficult to machine. Pure commercial titanium is sticky and can cause long chips when cutting, which can damage cutting tools. This is why drops can also occur during titanium machining. But with high-pressure coolant, chips can be removed while cutting and the equipment can be moved more easily, making it less difficult.
Short, interrupted cuts should be avoided when machining titanium; cutting tools should continue working as they encounter raw material. Too much tool contact can cause friction, which can build up excess heat and lead to work hardening. Lower speeds and higher feed rates will reduce heat build-up.
Processing titanium raw materials requires rigid machine setup and secure gripping. Why? Titanium and titanium alloys are highly ductile, can experience chatter and springback when cut, and may produce a less than impressive surface finish.
welded titanium
Welding titanium and titanium alloys is easy. The same welding techniques used for stainless steel also apply to titanium.
But here, tidiness and inert gas protection are crucial. Air pollution can cause problems with titanium welding.
Titanium uses
The aerospace and automotive industries use titanium for its impressive strength-to-weight ratio. 50% of the alloys used in aerospace engineering are Ti 6AI-4V. Motorcycles use titanium for their exhausts because it's lightweight, manages heat well, and comes in a nice color.
Titanium is suitable for:
naval ship
Sports Equipment
Medical industry
landing gear
missiles etc.
Inconel
The trade name for high-quality nickel-chromium alloys is Inconel. This material can also withstand alloy-type high temperatures (up to 2,000°F) with zero strength loss. This material is very suitable even at low temperatures.
The mechanical properties of Inconel at room temperature are excellent. So you know, Inconel grade 725 has a tensile strength of about 180 ksi; that's twice the strength of structural steel. Other alloys, such as Inconel 718, are toughened to withstand precipitation, making them stronger. Corrosion and its kindred: Corrosion, oxidation, corrosion cracking and crevice corrosion do not affect Inconel.
Inconel's excellent properties meet the needs of demanding applications. However, materials like Inconel are more expensive than titanium, stainless steel, and aluminum.
Machining Inconel
Due to its high strength, processing is challenging. Inconel is so hard that cutting tools can become damaged during machining and the material can twist and bend.
Immersing Inconel in a solution reduces the material's hardness and prevents cutting tool wear. For machining Inconel, ceramic tools are recommended as it provides fast and uninterrupted cuts, making the workflow more manageable. Pecking should be avoided as this can make the job challenging.
Welding Inconel
Inconel is not easy to weld due to cracks. But Inconel alloys can be welded like Inconel 625 - an alloy that is easy to fill quickly and is usually welded using tungsten inert gas (TIG). This welding technique usually does not require filler but works well for joining Inconel. That's why it's recommended.
Uses of Inconel
Inconel is the material of choice when harsh temperatures and corrosion are issues, especially when other metals are not resistant to oxidation and deformation caused by high temperatures.
Inconel has excellent high temperature and chemical resistance and is used in exhaust systems for racing cars, turbines, jet engines, and in the oil and gas, aerospace, and marine sectors where heavy machinery components are required.
