MMC Hammer

1
MMC Hammer

• Group members
• Ed Barnard
• Lizzie Hager
• Jenny Lichter
• Kevin McComber

2-26-04
2
Overview

• Goal
• Material Properties
• Centrifugal Casting Process
• Short Term Objectives
• Prototype Design and Mold
• Progress
• Upcoming Experiments

3
Goal

• The goal of our project is to manufacture a
  light-weight, high fracture toughness hammer
  using metal matrix composites.

4
Material Properties

• Conventional steel hammer
• Carpenter 20Cb-3 Stainless Steel
• MMC hammer
• SiC / Ti-6Al-4V, V()35
• SiC / 6061 Alum, V 0.48
• Important properties for a hammer
• Density
• Tensile strength
• Modulus
• Wear resistance
• Fracture toughness

5
Material Properties

• Conventional steel hammer Tensile measurements
  at RT
• MMC hammer Tensile measurements at 0 C

6
Centrifugal Casting Process
7
Centrifugal Casting Process
8
Pressure Vessel Calculations
Pmax 2200 psi 150 atm S. F. safety factor
2 ri inner radius 1 inch
Material sUTS (ksi) Outer radius lt sUTS gt Outer radius (sUTS)min
Brass 30-90 1.08 1.16
Stainless steel 60-150 1.04 1.08
Aluminum 45-80 1.07 1.10
Graphite 7-10 1.77 2.09
9
Short Term Objectives

• Making mold
• size
• stability
• Ceramic scaffold
• packing
• formation

10
Prototype design

• Hammer head
• simple design
• radially symmetric (conical)
• More complex designs can be implemented later

11
Prototype Mold

• Two-piece mold
• Conical to aid in the release
• Sealed with an O-ring and bolted shut
• Swagelok connector to runner

12
Prototype Mold
Top Mold
13
Progress

• Two ceramic layers per casting
• Investigating interfaces
• 2µm TiC has been eliminated
• Hardness tests

14
Upcoming Experiments

• Hardness test
• SEM
• Machine mold
• Find an effective break-out ceramic for mold
  release
• Use and test new ceramic particles

15
Projected Work Schedule
16
Works Cited

• Carpenter 20Cb-3 Stainless Steel, Bar.
  Accessed 22 Feb 2004. MatWeb.com, The Online
  Materials Database. 2004. lthttp//www.matweb.
  com/search/SpecificMaterialPrint.asp?bassnumNCAR9
  0 gt.
• Halstead, Gary. Pictures from Dictionaire
  Paisonné du Mobilier Français. Accessed 24
  February 2004. Medieval and Renaissance
  Woodworking. 2003. lthttp//www.medievalwoodworki
  ng.com/vld_tools.htm gt.
• Home gt Centrifuges lt Centrifuges, Floor gt RFQ
  Form. Accessed 23 Feb 2004. Used-Line.Com
  Used Hi- Tech and Scientific Equipment.
  lthttp//used-line.com/cgi-bin/used/4055271_/IEC_C
  RU_5000.htm gt.
• Koczak, et al. Metal-Matrix Composites for
  Ground Vehicle, Aerospace and Industrial
  Applications. Fundamentals of Metal Matrix
  Composites. Boston Butterworth-Heinemann, 1993.
  Eds. Suresh, S., Mortensen, A. and A.
  Needleman. 297-326.
• Poco Graphite AXM-5Q Specialty Graphite.
  Accessed 25 Feb 2004. MatWeb.com, The
• Online Materials Database. 2004.
  lthttp//www.matweb.com/search/SpecificMaterialPri
  nt.asp?bassnumNCAR90 gt.