Double-pulse laser micro sintering: Experimental study and mechanism analysis aided by in-situ time-resolved temperature measurements
Double-pulse laser micro sintering: Experimental study and mechanism analysis aided by in-situ time-resolved temperature measurements
复制标题
双脉冲激光微烧结：原位时间分辨温度测量辅助的实验研究和机理分析
DOI：
10.1016/j.jmapro.2021.05.071
复制
发表时间：
2021
影响因子：
6.2
通讯作者：
You, Haoxuan
中科院分区：
文献类型：
--
作者：
Liu, Weidong;Song, Hanyu;Wu, Benxin;You, Haoxuan
激光微烧结（LMS）是通过激光烧结制造微尺度部件和/或特征的工艺。小粉末颗粒（例如，大约1 μm）通常用于良好的空间分辨率。此外，由于相关的潜在优点，经常采用脉冲激光器。为了获得良好的机械性能，基于脉冲激光的LMS通常需要烧结材料的高度致密化，然而，这通常比常规的宏观选择性激光烧结或熔化更难以实现。作者提出了一种新的双脉冲激光微烧结（DP-LMS）工艺，这是一种新的基于脉冲激光微烧结的烧结材料致密化方法。它采用激光脉冲组，每个激光脉冲组包含“烧结激光脉冲”，然后是一定延迟时间的“压制激光脉冲”，分别用于烧结（熔化和聚结）粉末颗粒并在材料上产生高瞬态压力。本文报道了单道烧结的DP-LMS工艺的研究。相关的基本机制进行了分析与现场的时间分辨测量的粉末床表面温度在DP-LMS的帮助下。在所研究的条件下，发现DP-LMS比仅使用烧结或压制激光脉冲的LMS能产生更好的烧结结果。为了在DP-LMS中获得良好的烧结结果，“压制激光脉冲”需要具有足够高的强度，并且足够接近地跟随最后一个在前的“烧结脉冲”，使得被照射的表面区域仍然处于熔融状态（或部分地处于熔融状态到足够的程度）。DP-LMS中良好烧结结果的基本机制预期为“压制激光脉冲”可在粉末床表面上诱导（可能经由激光烧蚀和等离子体产生）高压，这可促进熔体流动、减少成球和/或增强材料致密化和/或连续性。此外，在DP-LMS过程中相邻的“烧结激光脉冲”之间的热积累效应已被揭示的原位温度测量。
Laser micro sintering (LMS) is a process of manufacturing microscale parts and/or features by laser sintering. Small powder particles (e.g., on the order of ~1 μm) are often used for good spatial resolutions. Besides, pulsed lasers are often employed due to related potential advantages. For good mechanical properties, pulsed laser-based LMS typically desires high densification of sintered material, which is, however, often more difficult to achieve than conventional macro selective laser sintering or melting. A new double-pulse laser micro sintering (DP-LMS) process was recently proposed by the corresponding author, which is a novel approach to potentially achieve good densification of sintered material in pulsed laser-based LMS. It employs laser pulse groups, each of which contains “sintering laser pulse(s)” followed by “pressing laser pulse(s)” at a certain delay time, which are used to sinter (melt and coalesce) the powder particles and generate a high transient pressure onto the material, respectively. This paper reports a study of the DP-LMS process for single-track sintering. The related fundamental mechanisms are analyzed with the help of in-situ time-resolved measurements of powder bed surface temperatures during DP-LMS. Under the conditions studied, it has been found that DP-LMS can produce better sintering results than those by LMS only using the sintering or pressing laser pulses. For a good sintering result in DP-LMS, the “pressing laser pulse” needs to have a sufficiently high intensity and follow the last preceding “sintering pulse” close enough such that the irradiated surface region is still in a molten state (or partially so to a sufficient extent). The fundamental mechanism for good sintering results in DP-LMS is expected to be that the “pressing laser pulse” can induce (likely via laser ablation and plasma generation) high pressures on the powder bed surface, which can promote melt flow, reduce balling and/or enhance material densification and/or continuity. In addition, a thermal accumulation effect between adjacent “sintering laser pulses” during DP-LMS has been revealed by the in-situ temperature measurements.
登录
查看更多内容
影响因子：
1.7
作者：
A. Fleitman;R. B. Herchenroeder;J. Chow
通讯作者：
J. Chow
双脉冲激光微烧结实验研究：一种新型激光微烧结工艺
影响因子：
3.9
作者：
Song, Hanyu;Kang, Zheng;Liu, Ze;Wu, Benxin
通讯作者：
Wu, Benxin
激光烧结分离且均匀分布的多壁碳纳米管集成铁纳米复合材料
影响因子：
3.2
作者：
D. Lin;C. Liu;G. Cheng
通讯作者：
G. Cheng
激光微烧结——粉末填充改进的品质飞跃
影响因子：
3.9
作者：
A. Streek;P. Regenfuß;R. Ebert;H. Exner;Fachbereich Mpi
通讯作者：
Fachbereich Mpi