Scholarlink

<p>This study explores recycling aerospace-grade Al7075 machining chips using Spark Plasma Sintering (SPS) to overcome environmental and energy inefficiencies in conventional aluminum recycling. The chips underwent magnetic separation, milling, sieving, and SPS at 450&#xa0;°C under 30&#xa0;MPa for 15&#xa0;min. Two conditions—annealed (S-7075-0) and T6 heat-treated (S-7075-T6)—were evaluated against cast references (7075-0 and 7075-T6). SPS produced near-theoretical densities (&gt; 99%), exceeding cast samples (98.93%), due to localized heating and pressure that reduced porosity and grain growth. The S-7075-0 exhibited a Vickers hardness of 126.5 HV and bending strength of 742&#xa0;MPa, vastly outperforming cast counterparts (55 HV, 260&#xa0;MPa). Enhancements stemmed from work hardening during milling, dissolution of MgZn<sub>2</sub> precipitates, and stronger interparticle bonds. S-7075-T6 matched conventional T6 hardness (148.8 HV vs. 147.7 HV) but had lower bending strength (613&#xa0;MPa vs. 675&#xa0;MPa), attributed to microstructural discontinuities. XRD confirmed partial dissolution of Zn, Mg, and Cu into the Al matrix, while SEM showed refined grain boundaries. The absence of contaminants during processing yielded superior mechanical properties compared to prior studies using commercial powders. These results validate SPS as a sustainable, low-energy method for high-quality recycled Al7075, avoiding drawbacks of traditional melting. Future work should optimize particle size and pre-compaction to enhance performance further.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Recycling of Aluminum 7075 Machining Chips by Spark Plasma Sintering Method

  • 期刊论文

  • 发表日期：

    2025年11月18日

查看全文
  • M. Akhavan Sedighy,
  • I. Mobashepour,
  • M. Zakeri,
  • M. Askari

摘要

This study explores recycling aerospace-grade Al7075 machining chips using Spark Plasma Sintering (SPS) to overcome environmental and energy inefficiencies in conventional aluminum recycling. The chips underwent magnetic separation, milling, sieving, and SPS at 450 °C under 30 MPa for 15 min. Two conditions—annealed (S-7075-0) and T6 heat-treated (S-7075-T6)—were evaluated against cast references (7075-0 and 7075-T6). SPS produced near-theoretical densities (> 99%), exceeding cast samples (98.93%), due to localized heating and pressure that reduced porosity and grain growth. The S-7075-0 exhibited a Vickers hardness of 126.5 HV and bending strength of 742 MPa, vastly outperforming cast counterparts (55 HV, 260 MPa). Enhancements stemmed from work hardening during milling, dissolution of MgZn2 precipitates, and stronger interparticle bonds. S-7075-T6 matched conventional T6 hardness (148.8 HV vs. 147.7 HV) but had lower bending strength (613 MPa vs. 675 MPa), attributed to microstructural discontinuities. XRD confirmed partial dissolution of Zn, Mg, and Cu into the Al matrix, while SEM showed refined grain boundaries. The absence of contaminants during processing yielded superior mechanical properties compared to prior studies using commercial powders. These results validate SPS as a sustainable, low-energy method for high-quality recycled Al7075, avoiding drawbacks of traditional melting. Future work should optimize particle size and pre-compaction to enhance performance further.