FORGING MEMBER, MANUFACTURING METHOD THEREFOR AND CONNECTING ROD

PROBLEM TO BE SOLVED: To provide a forging member excellent in strength, machinability, manufacturability and fracture splittability and capable of avoiding increase of raw material cost, a manufacturing method therefor and a connecting rod.SOLUTION: A forging member consists of an iron-based alloy having a chemical component containing, by mass%, C: 0.20 to 0.40%, Si: 0.01 to 0.20%, Mn: 0.30 to 1.60%, P: 0.030% or less, S: 0.040 to 0.150%, Cr: 0.50% or less, Al: 0.001 to 0.070%, V: 0.25 to 0.35%, Ca: 0.0100% or less, and N: 0.0150% or less and having index R1: 7.0 to 8.5. Charpy impact value by V notch is 10 to 20 J/cm. 0.2% bearing force is 600 MPa or more. R1=12.6×[C]+16×[P]+0.14×[S]+12×[V], where [X] represents percentage content of an element X.SELECTED DRAWING: Figure 1 【課題】強度、被削性、製造性、破断分割性に優れ、原料コストの増大を回避できる鍛造部品及びその製造方法並びにコンロッドを提供する。【解決手段】鍛造部品は、質量％で、Ｃ：０．２０〜０．４０％、Ｓｉ：０．０１〜０．２０％、Ｍｎ：０．３０〜１．６０％、Ｐ：０．０３０％以下、Ｓ：０．０４０〜０．１５０％、Ｃｒ：０．５０％以下、Ａｌ：０．００１〜０．０７０％、Ｖ：０．２５〜０．３５％、Ｃａ：０．０１００％以下、Ｎ：０．０１５０％以下を含有し、指数Ｒ１：７．０〜８．５である化学成分を有する鉄基合金からなる。Ｖノッチによるシャルピー衝撃値が１０〜２０Ｊ／ｃｍ2である。０．２％耐力が６００ＭＰａ以上である。Ｒ１＝１２．６×［Ｃ］＋１６×［Ｐ］＋０．１４×［Ｓ］＋１２×［Ｖ］上記式中［Ｘ］は元素Ｘの含有率を表す。【選択図】図１