Role of friction on the thermal development in ultrasonically consolidated aluminum foils and composites

Materials Science and Engineering: A

Masurtschak

et al. 2015

a b s t r a c tUltrasonic Additive Manufacturing (UAM) enables the integration of a wide variety of components into solid metal matrices due to the process induced high degree of metal matrix plastic flow at low bulk temperatures. Exploitation of this phenomenon allows the fabrication of previously unobtainable novel engineered metal matrix components.The feasibility of directly embedding electrical materials within UAM metal matrices was investigated in this work. Three different dielectric materials were embedded into UAM fabricated aluminium metalmatrices with, research derived, optimal processing parameters. The effect of the dielectric material hardness on the final metal matrix mechanical strength after UAM processing was investigated systematically via mechanical peel testing and microscopy. It was found that when the Knoop hardness of the dielectric film was increased from 12.1 HK/0.01 kg to 27.3 HK/0.01 kg, the mechanical peel testing and linear weld density of the bond interface were enhanced by 15% and 16%, respectively, at UAM parameters of 1600 N weld force, 25 mm sonotrode amplitude, and 20 mm/s welding speed. This work uniquely identified that the mechanical strength of dielectric containing UAM metal matrices improved with increasing dielectric material hardness. It was therefore concluded that any UAM metal matrix mechanical strength degradation due to dielectric embedding could be restricted by employing a dielectric material with a suitable hardness (larger than 20 HK/0.01 kg). This result is of great interest and a vital step for realising electronic containing multifunctional smart metal composites for future industrial applications.

Section: Introductionmentioning

confidence: 99%

Exploring the mechanical strength of additively manufactured metal structures with embedded electrical materials

Materials Science and Engineering: A

Masurtschak

et al. 2015

“…Firstly, the bulk temperature of the work piece during UAM process is less than half that of the melting point of the processed metals [16]. This acts to minimise potential thermal damage to vulnerable embedded components [17]. Secondly, a relatively large plastic metal flow, driven by ultrasonic welding, allows the fully embedding of functional components [18].…”

Section: Earlier Work In This Area Were Developed By Weiss and Prinzmentioning

confidence: 99%

Multifunctional metal matrix composites with embedded printed electrical materials fabricated by ultrasonic additive manufacturing

Composites Part B: Engineering

Nguyen

et al. 2017

This work proposes a new method for the fabrication of Multifunctional Metal Matrix Composite (MMC) structures featuring embedded printed electrical materials through Ultrasonic Additive Manufacturing (UAM). Printed electrical circuitries combining conductive and insulating materials were directly embedded within the interlaminar region of UAM aluminium matrices to realise previously unachievable multifunctional composites. A specific surface flattening process was developed to eliminate the risk of short circuiting between the metal matrices and printed conductors, and simultaneously reduce the total thickness of the printed circuitry. This acted to improve the integrity of the UAM MMC's and their resultant mechanical strength. The functionality of embedded printed circuitries was examined via four-point probe measurement.DualBeam Scanning Electron Microscopy (SEM) and Focused Ion Beam (FIB) milling were used to investigate the microstructures of conductive materials to characterize the effect of UAM embedding energy whilst peel testing was used to quantify mechanical strength of MMC structures in combination with optical microscopy. Through this process, fully functioning MMC structures featuring embedded insulating and conductive materials were realised whilst still maintaining high peel resistances of ca. 70 N and linear weld densities of ca. 90%.

“…Metallurgical bonding at the weld interface can typically be achieved at temperatures approximately 30-50% of the matrix absolute melting temperature [5]. This reduction in processing temperature avoids thermal stresses arising from mismatches in the coefficients of thermal expansions as well as melt points -a common feature in other metal additive manufacturing processes [9,10]. Furthermore, as the deposited material is not elevated above its melt temperature, as is the case in powder bed fusion techniques such as Selective Laser Melting (SLM) and Selective Laser Sintering (SLS), issues such as embrittlement, residual stress and distortion of parts are significantly reduced.…”

Section: Introductionmentioning

confidence: 99%

Solid-state additive manufacturing for metallized optical fiber integration

Composites Part A: Applied Science and Manufacturing

Capel

Christie

et al. 2015

a b s t r a c tThe formation of smart, Metal Matrix Composite (MMC) structures through the use of solid-state Ultrasonic Additive Manufacturing (UAM) is currently hindered by the fragility of uncoated optical fibers under the required processing conditions. In this work, optical fibers equipped with metallic coatings were fully integrated into solid Aluminum matrices using processing parameter levels not previously possible. The mechanical performance of the resulting manufactured composite structure, as well as the functionality of the integrated fibers, was tested. Optical microscopy, Scanning Electron Microscopy (SEM) and Focused Ion Beam (FIB) analysis were used to characterize the interlaminar and fiber/matrix interfaces whilst mechanical peel testing was used to quantify bond strength. Via the integration of metallized optical fibers it was possible to increase the bond density by 20-22%, increase the composite mechanical strength by 12-29% and create a solid state bond between the metal matrix and fiber coating; whilst maintaining full fiber functionality.