Industrial Processes II INDUSTRIAL PROCESSES II INDEN 3313 Lecture 4 – Completion of Finishing; Treatments, Coatings, and Cleaning

Industrial Processes II OVERVIEW Return of HomeworkReturn of Homework Questions to Start/ErrataQuestions to Start/Errata FinishingFinishing –Process Descriptions –Parameters/Impact on Surface Finish TreatmentsTreatments CoatingsCoatings CleaningCleaning

Industrial Processes II QUESTIONS TO START ?? Errata --

Industrial Processes II HONING IllustrationIllustration Groover Figure 26.19, p 675

Industrial Processes II HONING Comparison to GrindingComparison to Grinding –Universal Joints Enable Stone to “Follow the Hole” Highest Pressure/Abrasion at Smallest Diameters –Precision Hole Size, Finish Center Compliance Assured, Cross Hatched Pattern – Hold Lubrication in Hole –Process Parameters Abrasive Material Grit Size Pressure Used Adhesive Used (Bond) Hone Speed

Industrial Processes II LAPPING IllustrationIllustration Kalpakjian, Figure 25.31, p.815

Industrial Processes II LAPPING Comparison to GrindingComparison to Grinding –Both Lap and Work Move (Same Grain Never in Same Location on Workpiece Abrasives in Slurry –Low Pressure –Able to Move in Response to Cutting Forces –Process Parameters Abrasive Material Grit Size Slurry Consistency Lap/Work Speed

Industrial Processes II POLISHING DescriptionDescription –Fine Abrasive Powders Are Used to Coat Fabric, Leather, Felt, … Disks or Belts –Coated Disk or Belt Rubbed on Surface to be Finished –Fine Abrasives Remove Material –Friction Heating Softens and Smears Surface Layers

Industrial Processes II POLISHING Comparison to GrindingComparison to Grinding –Very Soft Backing Material (Cloth) –Fine Abrasives (May be in Slurry) –Low Pressure –Process Parameters Abrasive Material Abrasive Particle Size Backing Material Pressure Used

Industrial Processes II BUFFING DescriptionDescription –Similar to Buffing with Softer Backing and/or Softer and/or Finer Abrasives –Also Known as “Compounding” from the term “Buffing Compound” –Extremely Fine Surface Finish Obtainable

Industrial Processes II BUFFING Comparison to GrindingComparison to Grinding –Very Soft Backing Material (Cloth) –Very Fine Soft Abrasives (May be in Slurry) –Low Pressure –Process Parameters Abrasive Material Abrasive Particle Size Backing Material Pressure Used

Industrial Processes II ELECTRO-POLISHING DescriptionDescription –Placement of Workpiece in Electrolytic Solution –Application of Electrical Potential to Workpiece –Ions (Charge) Collects on Outer Surface of Part –Ions Go Into Solution (Dissolve) –Highest Surface Goes Into Solution Most Rapidly

Industrial Processes II ELECTRO-POLISHING Comparison to GrindingComparison to Grinding –Removal of Material via Electro-Chemical Means (NOT Shearing/Metal Cutting) –Process Parameters Electrolyte Used Strength of Potential (Voltage) Duration of Applied Potential –Can Use a Similar Process With Metal Grinding Wheel – Grinding Fluid is Electrolyte and Known as Electro Chemical Grinding

Industrial Processes II FLOAT POLISHING IllustrationIllustration Kalpakjian, Figure 25.32, p.816

Industrial Processes II FLOAT POLISHING Comparison to GrindingComparison to Grinding –Pressure Supplied by Magnetic Forces Magnetic (Metallic Abrasives) Pulled Onto Workpiece Via Strength of Magnetic Field Permanent or Electro-Magnets Used Used on Ceramic Ball Bearings Pioneered at OSU –Process Parameters Abrasive Material Grit Size, Slurry Strength of Magnetic Field Rotational Speed

Industrial Processes II BARREL FINISHING DescriptionDescription –Parts and (Dry Pellets) Abrasive are Placed into a Container –Container is Rotated –As Container Rotates the Parts Shift/Slide Against One Another (with the Abrasive Between Them) and the Weight of the Parts Provides the Pressure for the Abrasion Process.

Industrial Processes II BARREL FINISHING IllustrationIllustration Groover, Figure 32.2, p. 816

Industrial Processes II BARREL FINISHING Illustration Of Pellet ShapesIllustration Of Pellet Shapes Groover, Figure 32.3, p. 817

Industrial Processes II BARREL FINISHING Comparison to GrindingComparison to Grinding –Lower Pressure –Slower Speeds –Shaped (Loose) Abrasives –Process Parameters Abrasive Material Abrasive Pellet Shape Ratio of Parts to Abrasive Rotational Speed –Also Known as “Tumbling”

Industrial Processes II IllustrationIllustration Kalpakjian, Figure 25.33, p.818 ABRASIVE FLOW

Industrial Processes II ABRASIVE FLOW Comparison to GrindingComparison to Grinding –Lower Pressure –Slower Speeds –Abrasive Slurry –Process Parameters Abrasive Material Abrasive Slurry “Stiffness” Pressure Forcing Slurry Through/Around Part

Industrial Processes II ABRASIVE JET IllustrationIllustration Kalpakjian, Figure 26.20, p.847

Industrial Processes II ABRASIVE JET Comparison to GrindingComparison to Grinding –“Soft” Backing (Air) –Small Depths of Cut (Bounce Off) –Abrasive is “Loose” –Peens Surface –Process Parameters Abrasive Material Abrasive Particle Size and Shape Angle of Incidence –Also Known as Sand Blasting, Bead Blasting

Industrial Processes II SURFACE TREATMENT AND COATING GoalsGoals –Improve Hardness (Wear Resistance) –Reduce Adhesion –Improve (Retention) of Lubricants –Improve Corrosion Resistance Barrier Methods Insulation Methods –Improve Fatigue Resistance –Build-up/Restore Worn Surfaces –Modify Surface Smoother or Rougher Color

Industrial Processes II SURFACE TREATMENT DefinitionDefinition –Changes Metallurgy (Crystalline Structure) of Metallic Parts Using Pressure or Heat TypesTypes –Mechanical (Cold Working) Shot Peen/Hammer Peening –Hit Surface with Ceramic or Steel Shot or Hammer Roller/Ball Burnishing –Use Surface Rollers to Plastically Deform Surface Explosive Hardening –Use High, Transient Force Application to Cold Work Surface

Industrial Processes II SURFACE TREATMENT TypesTypes –Thermal Flame and Induction Hardening –No Material Added, Smaller Grains at Surface –Heat and then Cool Surface/Part –Usually an “Air Quench” Process Anneal – Heat/ Soften Surface via Annealing – Often Done in Furnace Case Hardening –Material Added, Carburizing, Nitriding,... –Heat To Assist in Diffusion into Surface then Cool Surface –Parameters »Temperature, Time, Pressure

Industrial Processes II COATINGS DefinitionDefinition –Processes which Add Materials to the Base Component(s) TypesTypes –Mechanical (Apply Particles onto Surface) Cladding –Roll Thin Layer onto Base Metal (Alclad, Zn Coated Steel Mechanical Plating –“Throw” Metal Particles/Powder onto Surface »Analogy – Snow Ball onto a Brick Wall Painting

Industrial Processes II COATINGS Types (cont.)Types (cont.) –Thermal (Coat w/Molten Material) Thermal Spraying (Metallizing) –Liquid Metal Spray Produced by Combustion/Heating to Melt Metal in Nozzle and use Escaping Gas to Expel Molten Metal at Speed onto (cool) Surface. –Parameters/Concerns »Temperature, Gas, Gas Pressures »Oxydation (vacuum) –Done at OKC Air Logistics Center to Rebuild Worn Jet Engines

Industrial Processes II COATINGS Types (Cont.)Types (Cont.) –Thermal Hard Facing –Harder Material Added to Surface –Melt a Filler Rod onto a Surface Rather Using an Electric Arc or Oxyfuel Heat Source –Often, Some Melting of Base Surface (Hot) Dipping –Dip part to be Coated in Molten Metal –Galvanization (Zn Coating) Enameling (Coat and Fuse with Heat) –Enameling of Steels, … –Glazing of Ceramics

Industrial Processes II COATINGS Types (cont.)Types (cont.) –Physical Vapor Deposition Vacuum Evaporation –Evaporate metal to be deposited at high temperature –Let condense on cool part –Uniform Coating (Simple and Complex Shapes) –Parameters »Temperature Difference, Exposure Time Sputtering –Use of ionized inert gas to bombard cathode, causing sputtering (ejection) of its atoms and subsequent condensation of the metal atoms on anode

Industrial Processes II COATINGS Types (cont.)Types (cont.) –Chemical Vapor Deposition Thermochemical process – a reaction produces desired coating in an inert atmosphere –TiN Coating of Cutting Tools –Chemical Electroplating, Plating, Electroforming –Deposition of ions from solution onto base »Electroplating, Electrical Current Used »Plating, No Current – Uses Reduction Reaction »Electroforming, Current, No Base Metal Coated –Parameters »Current Density, Voltage, Time »Part Shape (Affects Uniformity of Coating)

Industrial Processes II COATINGS TypesTypes –Chemical (cont.) Anodizing (Oxidizing Aluminum) –Produces porous oxide (hard) layer on surface via emersion of electrolytic cell in acid bath -- oxygen adsorption by metal – can add color (dyes) Conversion Coating (Surface Reactions) –Naturally occurring oxides are formed on surfaces via chemical or electrochemical reactions; colors can be produced from some reactions (black oxides on iron steels) Sol-Gels –OSU Research on corrosion resistance for aging aircraft

Industrial Processes II CLEANING DefinitionDefinition –Removal of Contaminants from Surfaces Dirt, Oils, Moisture, … TypesTypes –Mechanical Brushing (Wire) Blasting (Abrasive Jet) Tumbling Steam Ultrasonic

Industrial Processes II CLEANING TypesTypes –Chemical Solution (Dissolves Dirt into Solution) Saponification (Convert Oils to Soap) Emulsification (Suspend in Emulsion) Dispersion (Reduce Concentration, Dilute) Aggregation (Collect Particles, Remove Collection) Pickling (Acid or Alkaline to Dissolve)

Industrial Processes II QUESTIONS OR CLARIFICATIONS ???