CBN tool characteristics and machining case of automobile VVT gear
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The characters of CBN tools |
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The second hard thing in the world, very high hardness and high abrasive resistance. |
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High heat stability, it keeps hard even in the 1400 – 1500°C |
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Chemical stability. No oxidation in 1000 °C. No chemical reaction with ferrous metals even in 1200 – 1300°C. |
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Good thermal conductivity and low friction coefficient. |
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The advantages of CBN tools compare to other tools |
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Compare to Carbide tools |
CBN is harder than carbide tools, and its abrasive resistance is 30 – 50 times higher than carbide tools. |
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Compare to Ceramic tools |
The impact toughness and fracture resistance of CBN inserts are better. And CBN tools performs good in interrupted cutting for HRC 60 work pieces. |
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Compare to PCD tools |
Thanks to its chemical stability character, CBN tools is the first choice in cast iron, HSS and hardened steel processing. And its performance is maximized when processing temperature up to 1100°C. |
Study Case
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Finish cutting for automobile VVT gear |
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Workpiece material |
Hardened Powder Metallurgy |
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Workpiece hardness |
>HRC45 |
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Tools |
Coated CBN inserts, DCGW11T304 |
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Process mode |
Interrupted finishing |
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Coolant |
Oil cooling |
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Cutting speed |
175 m/min |
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Feed rate |
0.05 mm/rev |
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Cutting depth |
0.1 mm |
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Tool life |
260 pieces |
