1. Similarities
Alloy composition
Both are Al-Mg alloys, with a magnesium (Mg) content of 4.0–4.9% and a chromium (Cr) content of 0.05–0.25%. Other elements (such as iron, silicon, and copper) are strictly restricted.
Basic performance
Lightweight characteristics: The density is 2.7 g/cm³, which is suitable for weight reduction scenarios;
Corrosion resistance: Both have excellent resistance to seawater and salt spray corrosion, suitable for marine environments;
Welding performance: Supports argon arc welding, laser welding and other processes, and has a high strength retention rate after welding.
Applicable standards
Both comply with ASTM B209 specifications and are suitable for shipbuilding, pressure vessels, industrial structural parts and other scenarios.
2. Differences
State definition and processing technology
H111: Partial annealing (stabilization annealing) after cold working, retaining some work hardening effects and improving formability;
H112: Natural aging only after cold working, no annealing process, and a simpler process.
Mechanical properties
H111:
Tensile strength: 275–350 MPa
Yield strength: ≥210 MPa
Elongation: ≥16% (better plasticity)
H112:
Tensile strength: 275–350 MPa (equivalent to H111)
Yield strength: ≥215 MPa (slightly higher than H111)
Elongation: ≥10% (the balance between strength and plasticity tends to be high strength).
Surface quality
H111: Slight roller marks are allowed (depth ≤0.02mm), suitable for general industrial scenarios; H112: The surface is more uniform and dense, suitable for high-precision processing or parts with strict appearance requirements.
Applicable scenarios
H111: Preferred for structural parts that require complex forming, such as storage tanks, building frames, and deep-drawn parts; H112: More suitable for harsh corrosive environments (such as ship decks and offshore platforms) and cost-sensitive mass production.
