Measurement system and measurement method

A measurement system enabling measurement of an intensity distribution of diffracted X-rays obtained by irradiating a fillet portion of a metallic structure with X-rays, the metallic structure comprising:

• an axis portion;
• and a flange portion protruding radially from the axis portion, wherein the metallic structure comprises the fillet portion in a connection portion between the axis portion and the flange portion, the measurement system comprising:
• a diffracted X-rays measurement device provided with an irradiation unit that irradiates the fillet portion with X-rays;
• and
• a positioning device that positions the diffracted X-rays measurement device with respect to the fillet portion,
• wherein
• the positioning device comprises:
• a moving mechanism that moves three-dimensionally the diffracted X-rays measurement device relative to the fillet portion;
• and
• a rotation mechanism that rotates the diffracted X-rays measurement device in such a direction that an angle of incidence of the X-rays with respect to the fillet portion is changed,
• wherein a control unit controls movement by the moving mechanism and rotation by the rotation mechanism such that the diffracted X-rays measurement device does not come into contact with the axis portion and the flange portion,
• wherein the control unit controls the movement by the moving mechanism and the rotation by the rotation mechanism within such a range that the diffracted X-rays measurement device can detect a peak of diffracted X-rays,
• wherein, in a case in which:
• an axis passing through a fillet center and being parallel to a central axis of the axis portion is represented by an X-axis;
• an axis passing through the fillet center and being parallel to a protrusion direction of the flange portion is represented by a Z-axis:
• a coordinate of the fillet center is represented by (0, 0);
• a coordinate of a rotation center of the diffracted X-rays measurement device is represented by (X, Z);
• an irradiation distance of the X-rays by the diffracted X-rays measurement device is denoted by L [mm];
• a minimum value of the irradiation distance of the X-rays is denoted by Lmin [mm];
• a maximum value of the irradiation distance of the X-rays is denoted by Lmax [mm];
• a fillet angle is denoted by θ [°];
• a fillet radius is denoted by R [mm];
• an angle of incidence of the X-rays is denoted by Ψ [°];
• a distance between an end portion of a housing of the diffracted X-rays measurement device on the fillet portion side and the rotation center in the irradiation direction of the X-rays is denoted by h [mm];
• a top-to-bottom width of an end portion of the housing on a side adjacent to the fillet portion is denoted by W [mm]:
• a complementary angle of the Bragg angle is denoted by η [°];
• a top-to-bottom width of a detection region of a two-dimensional detector of the diffracted X-rays measurement device is denoted by D [mm];
• and an interval between the flange portion and an imaginary straight line which passes through the fillet center and is parallel to the flange portion is denoted by a [mm], the control unit controls the movement and rotation such that inequality 1 and inequality 2 are satisfied:
• (Lmin+h)sin(θ+ψ)−R sin θ≤X≤(Lmax+h)sin(θ+ψ)−R sin θ 1
• (Lmin+h)cos(θ+ψ)−R cos θ≤Z≤(Lmax+h)cos(θ+ψ)−R cos θ 2
• wherein with respect to an imaginary straight line which passes through a measurement site and the fillet center, the angle of incidence Ψ of the X-rays is defined to be positive in a case of tilting toward the axis portion, and is defined to be negative in a case of tilting toward the flange portion:
• in a case in which Ψ≥0, the irradiation distance L of the X-rays satisfies inequality 3;
• and in a case in which Ψ<0, the irradiation distance L of the X-rays satisfies inequality 4:
• -
• R
• ⁡
• (
• 1
• -
• cos
• ⁢
• θ
• )
• +
• W
• 2
• ⁢
• sin
• ⁡
• (
• θ
• +
• Ψ
• )
• cos
• ⁡
• (
• θ
• +
• Ψ
• )
• ≦
• L
• ≦
• D
• 2
• ⁢
• tan
• ⁢
• η
• 3
• R
• ⁢
• sin
• ⁢
• θ
• +
• W
• 2
• ⁢
• cos
• ⁡
• (
• θ
• +
• Ψ
• )
• -
• a
• sin
• ⁡
• (
• θ
• +
• Ψ
• )
• ≦
• L
• ≦
• D
• 2
• ⁢
• tan
• ⁢
• η
• .
• 4