Strand for saw wire and manufacturing method thereof

Abstract

Regarding contents of C, Si, Mn and Cr, a value of parameter P represented by the following (equation 1) is 1000 or more. A metallic structure contains wire-drawn pearlite in an area ratio of 98% or more, a diameter is 0.05 mm to 0.18 mm, a tensile strength is 4000 MPa or more, and a twist number in a twist test in which a grip-to-grip distance is 100 mm, and a tension equal to a tensile strength×a cross-sectional area of wire×0.5 is applied, is 5 or more.P=1098×[C]+98×[Si]−20×[Mn]+167×[Cr]  (equation 1)(in the (equation 1), [C], [Si], [Mn] and [Cr] indicate contents (mass %) of C, Si, Mn and Cr, respectively.)

Description

TECHNICAL FIELD[0001]The present invention relates to a strand for saw wire used for cutting a metallic material, a ceramic material, a semiconductor material and the like, and a manufacturing method thereof.BACKGROUND ART[0002]A saw wire is used for cutting Si single crystal, Si polycrystal, sapphire, SiC single crystal and the like. Further, a piano strand for saw wire, a steel strand for saw wire and the like have been proposed (Patent Literatures 1 and 2). The saw wire is required to have a small wire diameter and high strength.[0003]Further, a strand for steel cord used for reinforcing a tire, a belt and the like is also required to have a small wire diameter and high strength, similar to the saw wire. Further, various strands for steel cords have been proposed (Patent Literatures 3 to 9).[0004]As saw wires, there have been known a free-abrasive saw wire and a fixed-abrasive saw wire. The fixed-abrasive saw wire is formed such that an abrasive such as diamond is fixed on a stra...

AI Technical Summary

Benefits of technology

The present invention relates to a strand for saw wire and a manufacturing method thereof. The technical effect of the invention is to provide a strand for saw wire that can suppress wire breakage during cutting, which is a common problem and reduces the yield of the material being cut. The invention achieves this by addressing the twisting of the saw wire during cutting, which is the main cause of wire breakage, and by controlling the twist number in a twist test. Additionally, the invention addresses the suppression of structures other than wire-drawn pearlite, such as ferrite and bainite, and the suppression of wire drawing strain to improve the breakage resistance of the strand for saw wire. The invention also takes into account the content of elements such as carbon, silicon, manganese, and chromium in the strand for saw wire to achieve high strength while suppressing wire drawing strain.

Problems solved by technology

Sapphire and SiC single crystal are more expensive than Si single crystal.

However, when cutting of a material to be cut is performed by using a saw wire with a small wire diameter, the saw wire is likely to be broken during the cutting.

When the saw wire is broken during the cutting, the cutting has to be stopped at that point, which results in reducing the yield.

Therefore, the more expensive the material to be cut, the higher the necessity for suppressing the breakage of the saw wire.

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