汇报题目：参加2019 Materials Research Society Spring Meeting & Exhibit参会报告

汇报时间：2019年5月13日（星期一） 19:00

汇报地点：科技园西五楼北楼428会议室

汇报人：施建旭

会议名称：2019 Materials Research Society Spring Meeting & Exhibit

会议时间：22-26 April 2019

会议地点：Phoenix, USA

会议简介：The Materials Research Society (MRS) was established in 1973 by a visionary group of scientists who shared the belief that their professional interests were broader in scope than existing single-discipline societies and that a new interdisciplinary organization was needed. Today MRS is a growing, vibrant member -driven organization of over 14,000 materials researchers from academia, industry, and government, and a recognized leader in the advancement of interdisciplinary materials research. Headquartered in Warrendale, Pennsylvania (USA), MRS membership now spans over 80 countries. The MRS Spring Meeting attracts nearly 5,000 attendees. For more information on the Materials Research Society, please check the MRS Web site at www.mrs.org. We look forward to working with you at the 2019 Spring Meeting and trust it will prove to be a scientifically stimulating experience.

会议交流工作

Poster presentation: Rapid synthesis and fabrication of thermoelectric materials using advanced manufacturing technique

报告人：施建旭

参加论文信息

Title: Rapid synthesis and fabrication of thermoelectric materials using advanced manufacturing technique

Author: Jianxu Shi, Hualing Chen, Wanjun Wang

Abstract: The conventional forming processes of thermoelectric bulk materials, such as hot press, cold press, spark plasma sintering, plasma activated sintering and others, require thermoelectric alloyed powder as raw materials. While the conventional synthetic methods of thermoelectric alloyed materials require very long time of combination reaction due to slow heating and cooling processes. It typically needs a heat preservation of several hours to achieve uniformity of reaction using lower energy density of heat source. Consequently, the balance between performance and fabrication costs plays a vital role in thermoelectric application.

We report a rapid and scalable synthetic method of thermoelectric materials using selective laser melting (SLM) of powder bed with a thickness of 2mm. The mixed powders of thermoelectric element granule according to stoichiometric ratio are used as starting materials. Alloy was then formed using SLM method with very high energy density. Sb₂Te₃ bulk with the merit number ZT at 0.4 was SLM-synthesized. This is comparable with that of the Sb₂Te₃ bulk obtained using conventional melting technology. Bi_0.5Sb_1.5Te₃ bulk was also SLM-synthesized with its ZT at 0.64. The SLM-synthetic time of thermoelectric materials processed is less than 30 min, compared to tens of hours for conventional melting process. SLM-synthesized method therefore opens up a novel way for rapid, scalable and low-cost manufacturing thermoelectric materials.

On the other hand, an efficient fabrication method for thermoelectric composite materials with low cost is presented. The mixtures of P-type Bi_0.5Sb_1.5Te₃ (BST) powders and epoxy resin with different ratios were prepared and cold-pressed using a stainless steel die under 70Mpa for 3 min. The composite samples were then thermocured at 75℃ for 3 hours and tested. The composite samples demonstrated a much lower thermal conductivity of 0.55W m^-1 K^-1 in comparison with 1.48 W m^-1 K^-1 at 125℃ of the bulk BST material. The ZT of the composite samples was measured and compared with that of the conventional Bi₂Te₃-based ingot. This fabrication method significantly simplifies the process of thermoelectric materials compared with traditional preparation technique.