Application of Halnn CBN tool in machining High Speed Steel

Application of high speed steel materials

Typical parts: Since the advent of high-speed steel in 1903, it has been known for manufacturing metal cutting tools. With the 

rapid development of science and technology, the application range of high-speed steel has been expanding. Since the 1960s, 

Japan has succeeded in testing high-speed steel as a center for the automotive and bicycle industries. About 15% of the high-speed 

steel produced today is used to make molds.

Other applications: Semi-high-speed steel, which has appeared in recent years, is a kind of roll material. It has high hardness and 

high wear resistance similar to that of high-speed steel, and has excellent red-hardness properties. Therefore, high-speed steel 

and semi-high-speed steel are ideal for roll material. The high-speed steel roll is made of high-speed steel with high hardness, high 

red hardness, good wear resistance and hardenability as the working layer of the roll, and the forged steel, cast steel or ductile iron 

with toughness can meet the requirements as the core material of the roll, and a high performance roll that combines the two in a 

metallurgical or packaged manner.

                               


Cutting tool material for machining high speed steel

High-speed steel itself can be used as a cutting tool material. Therefore, to machining workpieces of High-speed steel, it is 

necessary to use a tool material with higher hardness than high-speed steel to process. That is the CBN tools. The following 

is Halnn CBN tools for machining high-speed steel. The tool materials developed are as follows:

Machining high speed steel case 1

Application of Halnn CBN tool in machining High Speed Steel
	Workpiece material: powder high speed tool steel (M2, M4, M5, M6)  Workpieces Hardness: HRC65-HRC68
Difficulties in machining:  Originally tried to use an imported brand of CBN tool, the effect is not satisfactory, mainly in the roughing of the CBN tool life is very short, due to the micro-deformation of the inner hole wall after vacuum heat treatment, resulting in the situation of chipping in interrupt cutting the CBN tool loss is enormous.
Halnn CBN Tool solutions: In view of the customer's trial of a CBN tool for high-speed tool steel with a hardness of HRC67-HRC65, high-temperature delamination on the upper surface of the CBN tool causes severe wear on the crater, which can only be processed 1 piece.
Finally, try the Halnn BN-H10 grade CBN tool(can withstand interrupted cutting), the cutting effect is very good, and it is changed to the cutting edge arc of R1.6, and one edge can machining 3-5 workpieces, the customer is satisfied.

Application of Halnn CBN tool in machining High Speed Steel
	Workpieces material: high speed steel of about HRC 67 degrees      Processing sequence: shown on the left
Difficulties in processing:   a. Due to the high cutting temperature, the CBN tool current used often loses the cutting edge, as right. b. The tool life is too short. At 600 r/m, thefeed rate is 0.02mm, the finish is quickly deteriorated, the tool change frequency is high,and the maximum service life of the tool is 37 pieces.The cutting speed was changed to 1000 r/m,but the tool life was lower.
Tool plan: 1. Redesign of tool structure: Due to the high hardness of high-speed steel processing, in view of the non-standard groove cutting tools used by customers, the rigidity is insufficient, and the cutting edge often chiooing after the tool is heated, so it is changed to the standard groove cutting tools structure 2. Cutting tool material: Halnn BN-H05 grade CBN tool is selected, due more resistant to high temperature and high hardness. there is no longer the case of unstable cutting size and roughness. The customer is very satisfied with the durability and cost of the tool.

Machining High speed steel case 3

Difficulties in processing:

The hardness is high, the machining allowance is large, the cutting resistance of the grooving is large, and some parts have 

interrupt cutting impact, and the cutting tool is easy to chip.

Trial test case:

It adopts Halnn solid CBN tool BN-S20 grade, and its tool life is 2 times that of a brand of CBN tool.

Halnn BN-S20 grade CBN tool machining High speed steel rolls
	Processing material: high speed steel Roll hardness HSD90 Tool type: BN-S20 RCMX120700 Cutting parameters: Fr=0.2mm/r, Vc=35m/min
Tool material	Tool life	Failure modes
Halnn BN-S20 grade CBN tool	25 Groove/edge ↑	Normal wear ★
A brand of CBN tool	12 Groove/edge	Breakage

Machining High speed steel case 4

Difficulties in processing:

Ultra-high hardness parts, large machining allowance, and severe interrupt cutting conditions, the cutting tool is easy to break 

and cannot be processed normally.

Trial test case:

The Halnn brazed CBN tool BN-H21 can withstand strong interrupted cutting without chipping.

Halnn BN-H21 grade CBN tool machining high speed steel
	Processing conditions: strong interrupt cutting outer circle Workpieces material: high wear-resistant powder high speed steel, HRC65; Tool type: BN-H21 CNGA120408 Cutting parameters: ap=0.15mm, Fr=0.1mm/r, Vc=35-60m/min, wet cutting
Tool material	Tool life	Failure modes
Halnn BN-H21 grade CBN tool	5pcs   ↑	Normal wear  ★
A Japanese brand PCBN	＜1pcs	Breakage