The H111 and H116 tempers of marine grade aluminum 5083 are both work-hardened aluminum alloy states, but their performance and applicable scenarios are significantly different due to differences in processing technology, especially in marine environments.

The following is a comparative analysis of 5083 h111 vs h116 from three aspects: core definition, performance difference and application scenario:

I. Temper definition and processing technology

- H111 temper:

Belongs to the "low degree of work hardening + partial annealing" state. That is, after the material is cold-processed, some internal stress is eliminated through appropriate low-temperature annealing (or natural aging), while retaining medium strength, plasticity and processability are improved. This temper is not specifically optimized for extreme corrosive environments, and is a basic state with strong versatility.

- H116 temper:

"Stabilized work hardening" state designed for highly corrosive environments such as the ocean. After the material is cold-processed, it undergoes special stabilization treatment (such as temperature-controlled aging or annealing) to significantly improve corrosion resistance (especially stress corrosion cracking resistance) while ensuring strength. It is a "special grade" state for marine grade aluminum.

II. Core performance differences of 5083 h116 vs h111

1. Mechanical properties

Key conclusion: H116 has significantly higher strength than H111 through a higher degree of work hardening and stabilization treatment, but slightly lower plasticity; H111 focuses more on "easy processing", with moderate strength but better plasticity.

2. Corrosion resistance (core difference in marine environment)

- H111:

It has the seawater corrosion resistance of marine grade aluminum 5083 alloy (because it contains about 4.5% Mg, forming a dense oxide film), but its resistance to stress corrosion cracking (SCC) is weak. In a long-term high-stress, high-salt spray environment, there may be a risk of cracking due to residual internal stress.

- H116:

Through stabilization treatment (such as controlling the annealing temperature), the microstructure is significantly optimized (reducing the precipitation of β-phase Mg₂Al₃), the resistance to stress corrosion cracking (SCC) is greatly improved, and the resistance to pitting and intergranular corrosion is better. It is a "corrosion-resistant enhanced" state specially designed for the marine environment.

- Standard basis:

The H116 temper is clearly required in marine standards such as ASTM B928 to be "suitable for load-bearing structures in marine environments", while H111 is not included in the mandatory standards for such harsh scenarios.

3. Processing and welding performance

- H111:

Better plasticity, better cold processing formability such as bending and stamping, suitable for complex shape parts (such as bending and cutting of non-load-bearing components inside the hull). After welding, due to good plasticity, cracks are not easy to occur near the weld, but the strength will decrease slightly after welding (about 10%-15%).

- H116:

Due to high strength and slightly lower plasticity, cold processing requires greater external force, and complex forming is slightly more difficult. However, the welding performance is stable, and the organization treated by stabilization after welding is not easy to cause a significant decrease in strength due to softening of the heat-affected zone, which is more suitable for welding structural parts.

4. Internal stress control

- H111:

Most of the processing internal stress is eliminated by partial annealing, and the risk of component deformation is low. It is suitable for non-load-bearing parts with high requirements for dimensional stability (such as cabin partitions and pipe brackets).

- H116:

Although it has been stabilized, it still retains a certain amount of internal stress (to ensure strength), and deformation needs to be controlled through subsequent aging or mechanical correction. It is more suitable for load-bearing structures (such as hulls, decks, and side frames).

III. Application scenario division

- H111 applicable scenarios:

Non-load-bearing structures inside ships (such as cabin partitions, ventilation ducts, guardrail frames), parts that require complex forming (such as curved decorative parts, light brackets), or scenes with low strength requirements but frequent processing (such as cutting and bending).

- H116 applicable scenarios:

Core load-bearing structures of ships (such as hull outer plates, decks, side outer plates, keel supports), parts exposed to seawater immersion/high salt spray environments for a long time (such as ballast tanks, gangways), and key structures that need to withstand wave impact, vibration and other loads.

Summary

If you need to take into account both processing convenience (such as bending, welding) and medium strength, and the application environment is a non-strongly corrosive area inside the ship, choose H111;

If it is used for high-stress structures such as the outside of the hull and ballast tanks that are in long-term contact with seawater, it is necessary to prioritize strength and stress corrosion resistance, and choose H116 (core recommended state for ships).

The difference between the marine grade 5083 h111 and 5083 h116 is essentially the difference between "universality" and "specialization for marine environments". H116 is the more core application temper of marine aluminum 5083 alloy in the shipbuilding industry.