JIS G3125 スパH
JIS G3125 SPA-H steel です 高強度, low-alloy structural steel と:
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Balanced 化学組成 for toughness and weldability
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機械的性質 suitable for bridges, ships, and industrial frames
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一般的なアプリケーション in construction, shipbuilding, と重機
- 説明
JIS G3125 SPA-H です 高強度, low-alloy structural steel standard widely used in construction, shipbuilding, and industrial engineering. It is the Japanese Industrial Standard (彼) equivalent of high-strength structural plates, designed for 高い靭性, 溶接性, と構造的信頼性.
1. Standard Overview
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標準: JIS G3125
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学年: スパH (Structural Plate – High strength)
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タイプ: Low-alloy, high-strength steel plate suitable for welded structures
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Focus: Combines high yield strength with good toughness at ambient temperatures
2. 化学組成
| 要素 | コンテンツ (%) | 関数 |
|---|---|---|
| 炭素 (C) | 0.12 – 0.18 | 強度を提供します |
| マンガン (ん) | 1.0 – 1.5 | 靭性と焼入性の向上 |
| リン (P) | ≤ 0.035 | 不純物管理 |
| 硫黄 (S) | ≤ 0.035 | 不純物管理 |
| シリコン (そして) | ≤ 0.50 | Enhances strength and oxidation resistance |
| 銅 (銅) | ≤ 0.25 | Slightly improves corrosion resistance |
| ニッケル (で) | トレース | Improves toughness in some cases |
| クロム (Cr) | トレース | Contributes to strength and surface quality |
主な機能: Low-alloy composition ensures 高強度, 溶接性, and good cold formability, while maintaining toughness.
3. 機械的性質
| 財産 | 代表値 |
|---|---|
| 降伏強さ (MPa) | ≥ 355 |
| 抗張力 (MPa) | 470 – 630 |
| 伸長 (%) | ≥ 20 |
| 衝撃靱性 | 周囲温度で良好 |
| 硬度 (HB) | 140 – 190 |
ハイライト:
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High load-bearing capacity for structural use
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Good ductility for forming and bending
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Weldable without preheating in most applications
4. Key Applications
| 業界 | 典型的な使用例 |
|---|---|
| 工事 | 橋, 構造梁, trusses, 枠組みを構築する |
| Shipbuilding | Hull plates, decks, offshore platform structures |
| 産業用 & エンジニアリング | Machinery frames, storage tanks, パイプライン |
| 重機 | Cranes, load-bearing frames, structural supports |
使用上の利点:
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High strength allows thinner sections for same load
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Toughness ensures safety under dynamic loads
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Weldable for complex structural fabrication
5. Comparison with Other Structural Steels
| 学年 | 降伏強さ (MPa) | Primary Use |
|---|---|---|
| スパH (JIS G3125) | ≥355 | High-strength welded structural plates |
| SPA-C | ≥315 | Medium-strength structural plates |
| S355 (で) | 355 | European structural equivalent |
| ASTM A572 | 345–450 | High-strength structural steel |
Observation: SPA-H is widely used in Japan and Asia for structural and shipbuilding plates where 強さ, 溶接性, and reliability 重要です.
