When both 1050 နှင့် 1060 are used for folding and storing kitchenware, after repeated bending, is there any difference in the time when fatigue cracks occur due to the difference in purity? How can the toughness be enhanced through the rolling process?

1. နိဒါန်း: Material Requirements for Foldable Storage Cookware Accessories and the Positioning of 1060 အလူမီနီယံ

Foldable storage cookware accessories (ဥပမာ, foldable pot handles, storage brackets) need to withstand 500-1000 cycles of 90° bending-recovery. Fatigue cracks are the primary failure mode (စာရင်းကိုင်ကျော် 60% of failures), with core requirements of “high toughness + fatigue resistance”.

Notably, 1050 အလူမီနီယံနှင့် 1060 အလူမီနီယံ for foldable storage cookware accessories both belong to commercial pure aluminum (per GB/T 3880.1-2012). Due to their lightweight nature (2.7g/cm³) and good processability, they collectively account for over 70% of base materials for such accessories. The key difference between the two lies in purity: 1050 aluminum contains 0.25%-0.40% each of Fe and Si, စဉ် 1060 aluminum for foldable storage cookware accessories has lower impurities (Fe/Si ≤ 0.20%). This purity difference alters the microstructure, thereby affecting the fatigue crack initiation time; ထိသော, the rolling process can regulate the microproperties of pure aluminum, further enhancing toughness and extending the fatigue life of 1060 aluminum for foldable storage cookware accessories.

This article analyzes the fatigue differences between 1060 aluminum for foldable storage cookware accessories and 1050 အလူမီနီယံ, proposes targeted rolling processes, and provides a basis for material selection of foldable accessories.

2. Impact of Purity Difference on Microstructure and Fatigue Performance

(1) Microstructural Differences (Cold-Rolled State)

First and foremost, the purity gap between 1050 နှင့် 1060 aluminum directly translates to distinct microstructural features, as shown in the table below:

(2) Differences in Fatigue Crack Initiation Mechanism

Turning to the fatigue behavior under repeated bending, the microstructural disparities lead to distinct crack initiation timelines:

1. 1050 အလူမီနီယံ: Macroscopic cracks (≥500μm) appear after 400-500 bending cycles. Due to stress concentration at impurity phase interfaces, microvoids connect rapidly, accelerating crack propagation.

2. 1060 Aluminum for Foldable Storage Cookware Accessories: Due to fewer impurities and more uniform grains, the material can absorb more deformation energy before cracking. Macroscopic cracks appear only after 550-650 bending cycles—15%-20% more cycles than 1050 aluminum before failure.

Importantly, this leads to a core conclusion: Due to its higher purity, 1060 aluminum for foldable storage cookware accessories has a 18%-21% later fatigue crack initiation time than 1050 aluminum after repeated bending, making it more suitable for high-frequency foldable accessories (ဥပမာ, outdoor foldable pots).

3. Experimental Verification of Fatigue Performance (Including 1060 Aluminum for Foldable Storage Cookware Accessories)

(1) Experimental Scheme

To empirically validate the above analysis, controlled experiments were designed to compare the fatigue performance of the two alloys:

• Samples: 1050 အလူမီနီယံ (H14 temper), 1060 aluminum for foldable storage cookware accessories (H14 temper); thickness 1.0mm (common thickness for accessories), size 100mm×20mm (standard bending test specimens);

• Testing: An electric bending machine was used (bending angle ±90°, speed 10 cycles/min); every 50 cycles, a microscope was used to observe the bending zone (central area), and the number of cycles when the first microcrack (≥50μm) appeared was recorded.

(2) Result Analysis

Analyzing the test results, clear differences in fatigue life emerged between the two alloys:

Clearly, experiments confirm that the fatigue life of 1060 aluminum for foldable storage cookware accessories is significantly superior to that of 1050 အလူမီနီယံ. Reduced impurity content and more uniform grain structure are identified as the core factors driving this advantage.

4. Rolling Process Optimization (အတွက် 1060 Aluminum for Foldable Storage Cookware Accessories)

(1) Principle of Process Regulation

Fundamentally, enhancing the toughness of 1060 aluminum for foldable storage cookware accessories relies on three key mechanisms: “grain refinement + texture optimization + residual stress relief”:

• Grain refinement: Reducing grain size to 2-3μm increases grain boundaries, which hinder crack propagation and promote uniform deformation;

• Texture optimization: Inducing the {111}<110> texture improves the material’s isotropic deformation ability during bending;

• Residual stress relief: Reducing residual stress to 30-40MPa avoids stress superposition during repeated bending.

(2) Rolling Scheme for 1060 Aluminum for Foldable Storage Cookware Accessories (Focus on Grain Refinement)

Specifically tailored to 1060 aluminum for foldable storage cookware accessories, the optimized rolling process includes four stages:

1. Hot Rolling Blooming: Conducted at 380-400°C with a reduction ratio of 55%-65% (reducing thickness from 20mm to 7-8mm), which preserves deformation energy for subsequent grain refinement;

2. Cold Rolling at Low Temperature: Performed at room temperature (25-30°C) တစ် ဦး နှင့်အတူ 20%-25% reduction per pass, achieving a total reduction ratio of 70%-75% (from 8mm to 2.0-2.5mm) to increase dislocation density;

3. Intermediate Annealing: Carried out at 290-310°C for 1-1.5h, with annealing every 2 ဖြတ်သန်း, to refine grains to 2-3μm;

4. Finish Rolling and Aging: A reduction ratio of 12%-18% (from 2.5mm to 1.0mm) was used, with a rolling speed of 5-8m/min to induce the target {111}<110> ယက်သား; finally, room-temperature aging for 24h relieved residual stress.

(3) Process Effects

နောက်ဆုံးမှာ, the optimized process yielded significant improvements in the material’s performance:

After optimization, 1060 aluminum for foldable storage cookware accessories exhibited: elongation increased from 25% သို့ 32%, hardness reduced to 28-30HV, and the number of cycles for macroscopic crack initiation extended from 580 သို့ 750 (+29.3%). This performance meets the requirements of high-frequency folding accessories.

5. Engineering Application Recommendations

(1) Matching with Accessory Types

For practical engineering applications, the selection of aluminum alloy should align with the usage frequency of the accessory:

• High-frequency accessories (ဥပမာ, outdoor foldable pot handles): Prioritize 1060 aluminum for foldable storage cookware accessories, adopt the optimized rolling process, and control the final thickness at 1.0-1.2mm to ensure a fatigue life of ≥700 cycles;

• Medium-to-low frequency accessories (ဥပမာ, household steam racks): 1050 အလူမီနီယံ (ကုန်ကျစရိတ်သက်သာတယ်။) can be used, or unoptimized 1060 aluminum for foldable storage cookware accessories can serve as a cost-effective alternative.

(2) အရည်အသွေးထိန်းချုပ်မှု

To ensure consistent performance in mass production, strict quality control measures are recommended:

• Microstructural inspection: အတွက် 1060 aluminum for foldable storage cookware accessories, grain size should be controlled at 2-3μm, and the volume fraction of impurity phases should be ≤0.12%;

• Performance sampling inspection: For every 1000 accessories produced, 5 should be sampled for bending tests, requiring the number of cycles for macroscopic crack initiation to be ≥500.

(3) Cost-Performance Balance

ထို့ အပြင်, balancing cost and performance is critical for market adoption:

The raw material cost of 1060 aluminum for foldable storage cookware accessories is 5%-8% အဲဒီထက် မြင့်တယ်။ 1050 အလူမီနီယံ. သို့သော်, after optimization, its fatigue life increases by over 20%, making it suitable for high-end cookware brands. For the mass market, 1050 aluminum or a “1060/1050 ပေါင်းစပ်” structure (balancing performance and cost) can be adopted.

6. Conclusion and Outlook

အကျဉ်းချုပ်မှာ, three key findings emerge from this study:

1. Performance Difference: Due to its high purity (Fe/Si ≤0.20%), 1060 aluminum for foldable storage cookware accessories has a 18%-21% later fatigue crack initiation time than 1050 အလူမီနီယံ, making it the preferred choice for high-frequency foldable cookware accessories;

2. Process Value: ဟိ “low-temperature cold rolling + multi-pass annealing” process specifically designed for 1060 aluminum for foldable storage cookware accessories can extend its fatigue life by 29.3% and significantly enhance toughness;

3. Future Directions: Looking ahead, further improvements can be achieved through microalloying (ဥပမာ, adding trace Zr to refine grains) or adopting a “1060/1050/1060 composite rolling” structure, which will expand the application scenarios of 1060 aluminum for foldable storage cookware accessories.

ခြုံ, this study clarifies the performance advantages and process optimization paths of 1060 aluminum for foldable storage cookware accessories, providing technical support for the upgrading of foldable cookware accessories toward “ရှည်လျားသောဝန်ဆောင်မှုဘဝ + lightweight design”.