| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a coated cutting tool insert used in metal machining, and to provide a texture-cured α-Al<SB POS="POST">2</SB>O<SB POS="POST">3</SB>layer. <P>SOLUTION: The alumina layer is characterized in improved toughness and adheres to a substrate covering its all functional part. A coated film is constituted of one or more heat resistance layers including at least one layer to be texture-cured α-Al<SB POS="POST">2</SB>O<SB POS="POST">3</SB>formed of columnar particles having a length/width ratio of 2 to 12 and having a 2 to 20 μm thickness. The α-Al<SB POS="POST">2</SB>O<SB POS="POST">3</SB>has a strong (0006) diffraction peak. Improved wear resistance and toughness are obtained when a texture coefficient (TC) in a (0006) reflection is larger than 1.33 ln h+2 (h denotes the thickness of the α-Al<SB POS="POST">2</SB>O<SB POS="POST">3</SB>layer) and when the surface of the α-Al<SB POS="POST">2</SB>O<SB POS="POST">3</SB>layer is subjected to wet blast until an Ra value lower than 1 μm. An alumina layer having a strong (0001) texture is applied to a bonding phase enrichment cemented carbide substrate. This combination contributes to an increase of wear resistance and toughness. <P>COPYRIGHT: (C)2013,JPO&INPIT |
