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SUMMARY OF RESEARCH RESULTS . Advanced Manufacturing Technology Research Laboratory (AMTReL) Liverpool John Moores University. INVESTIGATION OF THERMALLY TREATED RECYLED GLASS AS A VIBRATORY MASS FINISHING MEDIA : Performance and Characterisation . Sponsored by: Vibraglaz (UK) Ltd.
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SUMMARY OF RESEARCH RESULTS Advanced Manufacturing Technology Research Laboratory (AMTReL) Liverpool John Moores University INVESTIGATION OF THERMALLY TREATED RECYLED GLASS AS A VIBRATORY MASS FINISHING MEDIA: Performance and Characterisation Sponsored by: Vibraglaz (UK) Ltd April, 2012 Prepared by: Mr. PitipongBenjarungroj Supervised by: Dr. Michael M Morgan
Content • Introduction • Aims / Objectives • Problem Outline • Experimental programme • Results
Introduction • Mass finishing refers to the process technologies for generating edge and surface finishes on a wide range of metallic and non-metallic materials • Common edge and surface finish requirements include: deburring, descaling, surface smoothing, edge-break, radius formation, removal of surface contaminants from heat treatment and other processes, bright finishing, pre-plate or coating surface preparation.
Introduction: Mass finishing process • Energy is imparted to the abrasive media mass via a vibratory or rotary means to impart motion to it and to cause it to act on the surfaces. [process control parameters: vibration amplitude, frequency, (rotational speed)] • Common mass finishing processes include: vibratory bowl and linear; barrel, centrifugal barrel and centrifugal disk, and rotating barrel • Fluid (compound solutions) required for lubrication (-lower frictional forces and reduce wear), aid swarf removal, cleaning, ease handling
Introduction: Mass finishing process Vibratory Bowl Linear Vibratory Centrifugal disk Centrifugal barrel
Introduction: Mass finishing media • “Media” refers to the abrasive consumable elements used in mass finishing process. • The common media types include natural abrasives, synthetic random media, preformed ceramic and resin-bonded media, and metallic media. • The composition of a media determines whether it is a cutting or finishing type of media.
Introduction: Mass finishing media • Geometry largely depends on application
Vibratory Finishing Thermally TreatedRecycled Glass Media :A Report on outcomes of the first research with this innovative product
Introduction • The media under investigation is produced wholly from recycled glass. In its raw state it is in cullet form. The cullet is cleaned of contaminants and crushed. The cullet is then sieved and subsequently graded in a manner similar to that for abrasive grains. The source of glass is varied but is in general glass scheduled for landfill and most recently is predominantly window glass. :presently there is very little knowledge of the performance, capability or mechanical characteristics of this media
Introduction • Production control requirements: - mould technology (and release agents) - heating rate, critical temperature (Tmax), duration at Tmax, cooling rate / quenching Each have a strong effect on media quality Secret recipe! This understanding was not available prior to this research
Introduction Sample V-Cut media
New Media Benefits 6 key features that distinguish it from other media: • No binder required • Significantly higher percentage of abrasive • Density: plastic media < V-Cut < ceramic media • Strong green credentials and low environmental impact • Recyclable • Lower cost
Aim / Objectives • To acquire fundamental understanding of the material characteristics of the new development thermally treated recycled media • To obtain machining data over a range of machining conditions • Establish and compare performance of thermally treated recycled media with conventional media • Help develop new products for industrial usage • Help direct the company in identifying the right media for a given job
Materials characterisation • Replication methods for surface topography assessment • -identification of cutting edge density • -insight into wear mechanism Cannot use stylus methods –stylus wear and lack of information on surface features This understanding was not available prior to this research
Cutting edge density: Replication Technique Replication Jig and housing Microset 101 RTH Gun and Cartridge Thru section of replica Jig to lay flat the replica for measurement
CUTTING EDGE DENSITY - MEASUREMENT UniscanOpticalinterferometer
Cutting Edge density Date: 08.06.11 Code: A1 name: Original - 0 deg Ra: 120.72 um Rz: 1.66 um Rq: 167.55 um Rt: 1.95 mm Mesh: 12x12 (144) Sampling: 11.74 um Surface Area: 6 x 6 Total Cutting Edge: 27 %cutting edge: 18.75% (Larger scale view) Typical surface topography result showing Number of peaks at highest level of the surface
Cutting Edge Density Measurement Cutting edge measurement data for thermally treated glass media
Bearing Ratio Observation Typical surface topography results Bearing ratio results
Bearing Ratio Observation Typical surface topography results Bearing ratio results
Media Comparision V-Cut Ceramic Plastic 60x magnification (CAMApp - desktop equipment) Note Cutting edge density
SEM of Thermally Treated Glass SEM at 100x magnitude SEM at 1000x magnitude
Performance Assessment • Media Wear rate • Surface roughness , Ra (principal parameter measured) • Brightness observation and Visual inspection (Burr removal) • Cycle times
Performance Assessment V-Cut media used in studies Mitutoyo--Series 178 SJ 400 Surftests Mass Finisher (vibratory tumbler) used in studies
Surface Roughness Discussion media 780 is medium grade cutter / polisher Results are consistent with published data for conventional media (in-house comparative data being prepared) Limiting values indicate boundary of performance on particular material For example: If lower Ra is required with material = aluminium, then different grade (i.e. polisher) would be needed, though this would be achieved at the cost of lower material removal rate
Surface Roughness Discussion media 790 performs more as a polisher than media 780 The abrasive action of the media is evident in the early part of the graph – i.e. the cutting edges initially dig into and hence roughen the surface before finishing occurs This is not so evident with a harder material eg. MS or SS
Comparison study of thermally treated media and conventional media against industrial components Titanium alloy coupon Roughness observation of conventional media and thermally treated media on benchmark materials
Brightness observation and Visual inspection Brass before and after 10 minute of machining using Vibraglaz 790 Brass before machining Brass after machining using Vibraglaz 780
Brightness observation and Visual inspection Stainless (Virgin) • Mild Steel (machining time 15 minutes) • From left to right • Mild steel before machining • Mild steel machining with Plastic media • Mild steel machining with Vibraglaz 790
Brightness observation and Visual inspection • Aluminium (machining time 15 minutes) • From left to right • Aluminium before machining • Aluminium machining with Plastic media • Aluminium machining with Vibraglaz 790 • Aluminium machining with Ceramic media • Brass (machining time 15 minutes) • From left to right • Brass before machining • Brass machining with Vibraglaz 770
Brightness observation and Visual inspection Crank shaft before machining Crank shaft after machining