Abstract: A vehicle knuckle (1) includes a main body portion (10) for supporting an axle, a strut connecting portion (11) for connecting a strut, and an arm portion (12) for connecting the main body portion (10) and the strut connecting portion (11) and having a space (18) inside. The arm portion (12) includes a sidewall portion (120) for connecting the main body portion (10) and the strut connecting portion (11), and has a first through hole (17a) communicating with the space (18), at a coupling portion (12a) with the main body portion (10). The sidewall portion (120) is free of a through hole communicating with the space (18).

Abstract: A vehicle knuckle 1 includes a main body 10, a strut junction 11 that is positioned at a first side in an extending direction of an axle supported by the main body and fastens a strut damper, and an arm 12 that couples the main body to the strut junction. The vehicle knuckle has a continuous space 17 formed inside the strut junction and the arm. The arm has a first through-hole 17a on a wall 12a that couples an end 10d at the first side of the main body to the strut junction. The first through-hole is formed, with being adjacent to the end at the first side, at the side of the main body with respect to the center of a coupling position of the wall and the main body and a coupling position of the wall and the strut junction and is communicated with the space.

Abstract: A vehicle knuckle 1 includes a main body 10, a strut junction 11 that is positioned at a first side in an extending direction of an axle supported by the main body and fastens a strut damper, and an arm 12 that couples the main body to the strut junction. The vehicle knuckle has a continuous space 17 formed inside the strut junction and the arm. The arm has a first through-hole 17a on a wall 12a that couples an end 10d at the first side of the main body to the strut junction. The first through-hole is formed, with being adjacent to the end at the first side, at the side of the main body with respect to the center of a coupling position of the wall and the main body and a coupling position of the wall and the strut junction and is communicated with the space.

Abstract: A vehicle knuckle (1) includes a main body portion (10) for supporting an axle, a strut connecting portion (11) for connecting a strut, and an arm portion (12) for connecting the main body portion (10) and the strut connecting portion (11) and having a space (18) inside. The arm portion (12) includes a sidewall portion (120) for connecting the main body portion (10) and the strut connecting portion (11), and has a first through hole (17a) communicating with the space (18), at a coupling portion (12a) with the main body portion (10). The sidewall portion (120) is free of a through hole communicating with the space (18).

Abstract: A high rigid spheroidal graphite cast iron, comprising: more than 3.0% to less than 3.6% of C, 1.5 to 3.0% of Si, 1.0% or less of Mn, 1.0% or less of Cu, less than 0.03% of P, 0.02% to 0.07% of Mg, residual Fe and inevitable impurities, as represented by mass %, wherein a carbon equivalent (a CE value) calculated by the mathematical expression (1): CE=C %+Si %/3 in terms of C and Si contents is 3.6 to 4.3%, the Young's modulus is 170 GPa or more, the tensile strength is 550 MPa or more, and the impact value is 12 J/cm2 or more.

Abstract: A high rigid spheroidal graphite cast iron, comprising: more than 3.0% to less than 3.6% of C, 1.5 to 3.0% of Si, 1.0% or less of Mn, 1.0% or less of Cu, less than 0.03% of P, 0.02% to 0.07% of Mg, residual Fe and inevitable impurities, as represented by mass %, wherein a carbon equivalent (a CE value) calculated by the mathematical expression (1): CE=C %+Si %/3 in terms of C and Si contents is 3.6 to 4.3%, the Young's modulus is 170 GPa or more, the tensile strength is 550 MPa or more, and the impact value is 12 J/cm2 or more.

Abstract: A high rigid spheroidal graphite cast iron, comprising: 2.0 mass % to less than 2.7 mass % or more than 3.0 mass % to less than 3.6 mass % of C, 1.5 to 3.0 mass % of Si, 1.0% or less of Mn, 1.0 mass % or less of Cu, 0.02 to 0.07 mass % of Mg and the residual Fe and inevitable impurities, wherein a carbon equivalent (a CE value) calculated by the mathematical expression (1): CE=C (mass %)+Si (mass %)/3 in terms of C and Si contents is 2.8 to 3.2% within a first range from 2.0 mass % to less than 2.7 mass % of C and is 3.6 to 4.2% within a second range from more than 3.0 mass % to less than 3.6 mass % of C, and the Young's modulus is 170 GPa or more.

Abstract: A high rigid spheroidal graphite cast iron, comprising: 2.0 mass % to less than 2.7 mass % or more than 3.0 mass % to less than 3.6 mass % of C, 1.5 to 3.0 mass % of Si, 1.0% or less of Mn, 1.0 mass % or less of Cu, 0.02 to 0.07 mass % of Mg and the residual Fe and inevitable impurities, wherein a carbon equivalent (a CE value) calculated by the mathematical expression (1): CE=C(mass %)+Si (mass %)/3 in terms of C and Si contents is 2.8 to 3.2% within a first range from 2.0 mass % to less than 2.7 mass % of C and is 3.6 to 4.2% within a second range from more than 3.0 mass % to less than 3.6 mass % of C, and the Young's modulus is 170 G or more.