As any seasoned driver knows, it is arguably the most important component of an engine. It’s the long, twisty, rotating rod, the crankshaft, by its own crazy rotation, drives our engine to run. But have you ever thought about the question, why does this crazy spinning crankshaft not wear out? What is special about the material used to make the crankshaft?
There are two things that make crankshafts so strong. The first is the different materials they use, and the second is the different surface treatments 39bet-kết quả bóng đá-kết quả xổ số miền bắc-kèo bóng đá -soi cầu bóng đá-đặt cược. Next I will explain these two points in detail for you, because the crankshaft is compressed too strongly during operation. Therefore, we have very strict requirements for the crankshaft, that is, its stiffness and strength must be enough, and its surface wear must be strong.
Stiffness and strength, how do we solve that? From the material aspect. Therefore, in order to manufacture crankshafts, we generally choose ductile iron and carbon steel and other materials with very strong stiffness.
Here friends, may want to ask, what ductile iron and carbon steel are? Medium carbon steel is well understood as a type of steel with a carbon content between low carbon steel and high carbon steel. To be precise, it contains between 0.25% and 0.60% carbon.
Carbon steel is what to solve. Here it is time to explain what ductile iron is. As the name suggests, ductile iron is a kind of cast iron material, not steel, but its performance is very close to steel. This material has high strength, abrasion resistance, and toughness, and is the best choice for crankshaft production. Then why is it called spheroidal ink? As a kind of iron-carbon alloy, the carbon content of ductile iron is much higher than 2.11%, and the form of this carbon precipitation is often graphite, and the appearance is spherical, so this is why it is called spheroidal ink. In the field of ductile iron, China has been in the forefront of the world, especially through the addition of rare earth, greatly improving the properties of ductile iron.
The first reason why the crankshaft is so strong, we have solved, now to the second reason, that is the surface treatment process. We should have all heard of surface treatment technology. The most important is surface quenching (CUI) fire, and in the crankshaft we surface quenching, generally is the crankshaft connecting rod neck and other places where the friction is particularly large.
So what is surface quenching? In simple terms, the steel is heated to a critical temperature and then allowed to cool rapidly. What does that do? The technical term is to austenize the steel and then go through the martensitic transformation, which sounds very complicated, but we just need to remember that by quenching the steel you can make it harder, more resistant, more resistant to corrosion.