Aluminum/calcium deformation metal-metal composites Charlie Czahor - - PowerPoint PPT Presentation

▶
aluminum calcium
SMART_READER_LITE
LIVE PREVIEW

Aluminum/calcium deformation metal-metal composites Charlie Czahor - - PowerPoint PPT Presentation

Aug 17, 2022 147 likes •296 views

Aluminum/calcium deformation metal-metal composites Charlie Czahor WESEP 594 Seminar March 8, 2018 Overview Background and Motivation Sample Preparation Recent Results Microstructure/Conversion Conductivity Tensile

slide-1
SLIDE 1

Aluminum/calcium deformation metal-metal composites

Charlie Czahor WESEP 594 Seminar March 8, 2018

slide-2
SLIDE 2

Overview

  • Background and Motivation
  • Sample Preparation
  • Recent Results

– Microstructure/Conversion – Conductivity – Tensile Strength

  • Prospects for Installation
  • Conclusions and Future Work
  • E. Morhardt, “Power Transmission: the Rise of the Supergrid”, The

Economist, 2017, pp. 71-72. 2

slide-3
SLIDE 3

Background and Motivation

  • Objective: Develop cost competitive, lightweight, high strength,

high conductivity material for overhead power transmission.

  • Increasing renewable generation capacity in remote areas requires

long distance transmission to reach population centers.

  • High voltage direct current (HVDC) is the preferred technology for

long distance transmission.

3

slide-4
SLIDE 4

Current High Voltage Conductor Designs

  • Aluminum Conductor Steel Reinforced (ACSR)
  • All Aluminum Alloy Conductor (AAAC)
  • Aluminum Conductor Composite Core (ACCC)
  • Aluminum Conductor Composite Reinforced (ACCR)
  • Aluminum Conductor Aluminum-Alloy Reinforced (ACAR)

4

ACCR AAAC ACCC ACAR ACSR

ACSR catalog, 2012, Southwire, Carrollton, GA.

slide-5
SLIDE 5

An Alternative Approach

  • Deformation Metal-Metal Composites

(DMMCs) can achieve both high strength and high conductivity.

  • DMMCs utilize ductile metals in both

the matrix and reinforcement phase.

  • Extensive deformation allows filaments to

reach sub-micron level.

  • High strength with no steel core.

5

Alan Russell, Scott Chumbley, Yu Tian, Adv. Engr. Matl., 2 (2000) 11-22.

Element Conductivity (IACS) Cost Density (g/cm3) Aluminum 61.0 Low 2.7 Calcium 48.7 Medium 1.5

Unconverted Al/Ca 11.5 vol. % Converted Al/Al2Ca 18 vol. %

50 µm

slide-6
SLIDE 6

Sample Preparation

6

High purity atomized Al (88.5 vol. %) High purity fine atomized Ca (11.5 vol. %) Blended powder compact Extrusion can loaded with compacts E-beam welding Indirect Extrusion

slide-7
SLIDE 7

Electrical Conductivity

  • Close to rule of

mixtures value at low strain

  • Drop in

conductivity at high strain from scattering at interfaces

  • Conversion to Al2Ca

surprisingly has little effect

7

29 30 31 32 33 34 35 36 6 7 8 9 10 11 12 13 Conductivity (µΩm-1) True Strain

Unconverted Converted 11.5% Ca ROM 18% Al₂Ca ROM

slide-8
SLIDE 8

Ultimate Tensile Strength

  • Hall-Petch

strengthening with smaller filament size

  • Al2Ca reinforced

wire stronger for all sizes

8

Unconverted Converted Filament Thickness

50 100 150 200 250 300 350 400 450 500 6 7 8 9 10 11 12 13 14 UTS (MPa) True Strain

Al/Ca 11.5% Al/Ca 11.5% Hall-Petch Al/Al₂Ca 18% Al/Al₂Ca 18% Hall-Petch ACSR ACCC ACCR ACAR

slide-9
SLIDE 9

Comparison to Existing Conductors

  • Specific strength as

great as two times that of ACSR

  • Able to tailor

composite properties for a specific application

  • Modified properties

with monolithic construction

50 70 90 110 130 150 50 52 54 56 58 60 Specific Strength (kPa m3kg-1) Electrical Conductivity (%IACS) Al/Al2Ca 18% ACSR ACAR ACCR ACCC

9

slide-10
SLIDE 10

Potential Savings Using Al/Al2Ca Composites

10

1000 2000 3000 4000 5000 ACSR Case 2 Number of Towers

  • 11.1%

500 1000 1500 ACSR Case 1 First Year Losses (GWh)

  • 12.4%

Scenario Constant with base case Varied ACSR As built As built Case 1 Tower spacing and weight per tower Conductor Size Case 2 Losses and weight per tower Tower spacing and Conductor Size Design Parameters Conductor Cross Section 1171 mm2 Voltage ±500 kV Rated Power 3100 MW Number of Towers 4200 Current 3100 A

slide-11
SLIDE 11

Ongoing and Future Work

  • Development of gas-phase passivation for

use during atomization of Ca powder.

  • Enabling industrial production of high purity

Al powder.

  • Commercial extrusion sample for size

conductor testing

11

slide-12
SLIDE 12

Conclusions

  • Metal-metal composites have potential to be used as
  • verhead conductors.
  • Converted Al/Ca composite were produced with high

strength, high electrical conductivity, and low density.

  • Weigh reduction and high strength can increase tower

spacing.

  • Several steps remain to move technology forward.

12

slide-13
SLIDE 13

Acknowledgements

Al/Ca Wire Team

Trevor Riedemann

  • Dr. Iver Anderson
  • Dr. Alan Russell

Ames Lab Powder Group

  • Dr. Iver Anderson

Ross Anderson Dave Byrd Stephanie Choquette Aaron Kassen Emily Rinko Tim Prost Trevor Riedemann Jordan Tiarks Stacey Trytek

  • Dr. Emma White

Other Contributors

Extrusion: Soren Mueller-(TU Berlin) Tensile Testing: Charles Spellman (Psylotech), Matt Besser(Ames Lab) Conductivity: Gaoyuan Ouyang (Ames Lab)

13

DE-AC02-07CH11358