Non-alloy steel (carbon content below 0.55%): The battle against chip breaking

When turning non-alloy steel, chip breaking is like a stubborn "roadblock," and it is also prone to forming built-up edges. In the delicate work of precision part machining, overcoming the challenges of chip formation and breaking requires increasing the feed rate. Excessive built-up edges can shorten tool life. Increasing the cutting speed can reduce the occurrence of built-up edges, ensuring smooth machining.

In this process, some key considerations for tool selection have been summarized: First, the tool coating is crucial; wear-resistant coatings can resist the erosion of built-up edges and extend tool life. Second, the tool's rake angle should not be too small; an appropriate rake angle helps chips flow out smoothly, reducing clogging.

Low-alloy steel: Clever tricks to combat wear

The machinability of low-alloy steel depends on heat treatment (hardness) and alloy content. During turning, the most common tool wear is flank wear and crater wear. Therefore, tools with extremely high resistance to flank wear should be preferred.

When selecting such tools, attention should be paid to the tool body material; high-quality carbide tool bodies provide solid support for wear resistance. Additionally, the tool's edge sharpness retention should be good; otherwise, frequent sharpening will delay work and affect overall efficiency.

High-alloy steel: No fear of high-temperature deformation

High-alloy steel is similar to low-alloy steel in that the higher the alloy content and hardness, the lower the machinability. When turning precision parts made of high-alloy steel with a hardness of HB450, the cutting zone instantly becomes a "steaming pot," prone to causing plastic deformation. Therefore, tools with high resistance to plastic deformation and cutting edge strength should be considered.

When selecting tools, attention should be paid to the tool's heat dissipation structure; good heat dissipation design can prevent high-temperature accumulation and avoid rapid tool softening. Additionally, the compatibility between the tool and the workpiece must be precisely considered; different shapes and specifications of high-alloy steel workpieces require targeted tool matching to achieve high-quality cutting.