A composite sintered material includes: cubic boron nitride grains; and hexagonal boron nitride grains or the hexagonal boron nitride grains and wurtzite type boron nitride grains, wherein a dislocation density of the cubic boron nitride grains is more than or equal to 1×10.sup.15/m.sup.2 and less than or equal to 1×10.sup.17/m.sup.2, a median diameter d50 of equivalent circle diameters of the cubic boron nitride grains is more than or equal to 10 nm and less than or equal to 500 nm, and a relationship of the following expression 1 is satisfied:
0.015≤(Vh+Vw)/(Vc+Vh+Vw)≤0.5,  Expression 1:
where Vc represents a volume-based content ratio of the cubic boron nitride grains, Vh represents a volume-based content ratio of the hexagonal boron nitride grains, and Vw represents a volume-based content ratio of the wurtzite type boron nitride grains.

A composite sintered material includes: cubic boron nitride grains; and hexagonal boron nitride grains or the hexagonal boron nitride grains and wurtzite type boron nitride grains, wherein a dislocation density of the cubic boron nitride grains is more than or equal to 1×10.sup.15/m.sup.2 and less than or equal to 1×10.sup.17/m.sup.2, a median diameter d50 of equivalent circle diameters of the cubic boron nitride grains is more than or equal to 10 nm and less than or equal to 500 nm, and a relationship of the following expression 1 is satisfied:

0.015≤(Vh+Vw)/(Vc+Vh+Vw)≤0.5,  Expression 1

where Vc represents a volume-based content ratio of the cubic boron nitride grains, Vh represents a volume-based content ratio of the hexagonal boron nitride grains, and Vw represents a volume-based content ratio of the wurtzite type boron nitride grains.

Provided are a metal wire rod drawing die that has a longer life than conventional dies and that can prevent damage to a metal wire rod surface and a method for manufacturing the die. In a metal wire rod drawing die (1), a die hole (2) for inserting a metal wire rod is formed. Where Ra1 represents a surface roughness of an inner surface of the die hole from a bearing section (2b) to an approach section (2a) corresponding to an area reduction rate of 30% in an axial direction of the die hole, Ra2 represents a surface roughness of the inner surface of the die hole from the bearing section to the approach section corresponding to the area reduction rate of 30% in a direction orthogonal to the axial direction of the die hole, and Ra3 represents a surface roughness of an inner surface of the bearing section of the die hole in the axial direction of the die hole, the Ra1, the Ra2, and the Ra3 satisfy a relationship represented by 0.14 m>Ra2>Ra1>Ra3.

Provided are a metal wire rod drawing die that has a longer life than conventional dies and that can prevent damage to a metal wire rod surface and a method for manufacturing the die. In a metal wire rod drawing die (1), a die hole (2) for inserting a metal wire rod is formed. Where Ra1 represents a surface roughness of an inner surface of the die hole from a bearing section (2b) to an approach section (2a) corresponding to an area reduction rate of 30% in an axial direction of the die hole, Ra2 represents a surface roughness of the inner surface of the die hole from the bearing section to the approach section corresponding to the area reduction rate of 30% in a direction orthogonal to the axial direction of the die hole, and Ra3 represents a surface roughness of an inner surface of the bearing section of the die hole in the axial direction of the die hole, the Ra1, the Ra2, and the Ra3 satisfy a relationship represented by 0.14 m>Ra2>Ra1>Ra3.