Laser Coating Removal and Surface Preparation Technologies and Equipment

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1 Laser Coating Removal and Surface Preparation Technologies and Equipment

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3 1 Very short, high irradiance laser pulse Coating Substrate Laser Ablation Coating Removal 4 Pyrolizing continues Heat conduction rapidly dissipates Evacuation system pulls ejecta away 2 Heat conduction begins 5 3 Organic material rapidly pyrolizes Heat conduction 6 Ablation cavity remains, ejecta captured by evacuation system

4 General Lasertronics Scanning XY Path of Laser O.7 mm ablated spot Laser Beam pulses 5,000-50,000/sec Coating Substrate Color Selective Laser Ablation Target surface inspected before each laser pulse If prohibited color detected, laser pulse is suppressed If desired color is detected, laser is pulsed Substrate exposed during prior passes

5 Scanning Alternatives Lasertronics Rotary Scan Lasertronics Uniform Two Axis Raster Scan Competitors Simple One Axis Scan (Over and under stripping)

6 GLC Laser Ablation Equipment Equipment can be rack, vehicle mounted or fixed Laser Umbilical Cable ( feet) Remote Portable Work Head Chiller Electrical Controls Waste Collection Control Cables Units are modular and can be separately sourced Fiber Optic Waste Collection Hose Work Head Work head can be handheld, suction-mounted or robot-mounted

7 Typical handheld system (Installation at Patuxent River, MD)

8 Surface Treatments Coating Removal Selective Layering Contouring Texturing

9 Handheld Tools H Series - Confined Space W Series - Color Selective

10 Strong Intellectual Property Position Extensive intellectual property portfolio including patents trade secrets and know-how Patents Issued Method & apparatus for ablating surface material Method & apparatus for ablating interior cylindrical surfaces Method & apparatus for rotary laser workhead Apparatus for color selection using laser scanning optics Method for detecting metal to control laser pulsing Method for color selection using laser scanning optics Method for color selection in Japan Apparatus for color selective stripping UV ablation plus improved scanning and recognition composite surfaces Color sensing for laser decoating in UK Color sensing for laser decoating in France Color sensing for laser decoating in Germany Color sensing for laser decoating in Canada Selective stripping using color recognition in EU Applied Laser ablation of DLC, CMAS and Hexavalent Chromium Enhanced scanning techniques and surface roughness control Fail safe closed loop control technique Alternative sensing technique for color sensing Laser film debonding Selective ablation of composite manufacturing mold release

11 Fixed-Wing Maintenance GLC Capabilities: Maintenance Tasks: Aircraft structure: Coating removal to metal Coating removal to primer Sealant removal Rust/corrosion removal Engine contaminant removal Surface preparation for coating Surface preparation for bonding Coating/corrosion removal from recesses & complex surfaces Repaint Paint removal for NDI/NDT Corrosion management Reseal/caulk CMAS removal Degrease Leveling compound removal Skin Exterior Cabin Interior Fuel Cells Lap & Butt Joints Door Sill Frames Keel Beams Castings and Mounting Lugs Landing Gear Engine Hot Sections

12 Boeing 737 Lap/Butt Joint Scribe Line Detection Requirement: Remove sealant from lap/butt joints without fuselage damage Ensure scribe line/incipient fractures are not obscured or distorted Current method: Solvent softening and scrubbing or scraping of the sealant Motivation: Current process too slow (24-48 hours), scrubbing can fill or obscure scribe marks FAA AD requires complete initial inspection, periodic re-inspection Boeing 737 Experience: Successful 5-cycle strip tests qualify GLC laser process for FAA certification Enabling Technology: Fiber-delivered laser ablation energy (GLC patents) Metal (Aluminum) detection and protection (GLC patent pending) Closed loop firing interrupt ensures material safety (GLC patent pending) Certification: FAA-approved GLC laser process is an Alternate Means of Compliance (AMOC) satisfying AD requirements for all metal aircraft regardless of manufacturer Fatigued structure of Aloha Airlines Flight 243 The Culprit joint scratches become cracks Solvent/scrub obscures scribe (UAL 737 micrograph) Lasertronics FAA-approved workhead in action

13 Federal Aviation Administration Transport Airplane Directorate Aircraft Certification Services Approves the GLC Laser Process Initial Approval for B-737 July 21, 2006, ZA Process Approval for B-737 August Global Approval for ALL airframe structures May FAA approves the GLC Laser Process as Alternative Method of Compliance (AMOC) to sealant stripping procedures specified in Boeing Alert SB A1262 Appendix A required by paragraph (f) of AD (Airworthiness Directive) for Boeing 737 Classic aircraft FAA approves the use of the GLC Laser Process for the removal of paint, sealant, corrosion and rust on metal substrates listed in SAE MA4872 Annex D: 2024 T3 clad Aluminum 7140 T351 and T7351 T1 6AI-4V Titanium 2024 T3 bare Aluminum AZ31B Magnesium 4340 Steel FAA approves the use of the improved GLC ZA Laser Process as an AMOC for the same AD since the GLC ZA Laser Process has demonstrated outstanding results in critical aerospace coating removal and surface-prep applications FAA clarifies and extends approval to all metallic aircraft structures, regardless of manufacturer, the Seattle Aircraft Certification Office has no objections to the use of the GLC ZA Laser Process Specification on airframe structure.

14 Cumulative Savings $M Fuel Tank Cleaning Requirement: Remove sealant from restricted fuel tank cells to facilitate inspections Current methods: Hand scraping, chemical stripping or water jet Motivation: Current processes are slow, poor quality, FOD/corrosion hazard Experience: Pacific Northwest Nat l Lab/LMCO/USAF feasibility study shows 3 day turnaround vs.10 days for current processes, payback after 5 aircraft Enabling Technology: Fiber-optic-delivered laser energy (GLC patent) Typical Fuel Tank Form, Fit and Function(s) of small rotary workhead (GLC patent) Closed loop firing interrupt ensures material safety (GLC patent pending) Certification: USAF Suitability for Flight Line Operation, focus on fire and personnel safety (One of) Lasertronics confined-space workhead tools Laser-cleaned fasteners Battelle PNNL / LMCO / USAF study (2006) Payback cost after 5 A-10 aircraft tanks Process 125 a/c, cost savings > $15 Million during laser expected lifetime $15 Million Number of Aircraft 5 125

15 Multilayer Coating Maintenance Requirement: Selectively strip multiple coating layers Current method: Hand sanding ( jitterbug sander ) Motivation: Current process too slow, control is poor, causes damage or overstripping of low observable coatings and/or underlying substrate Experience: Lasertronics has demonstrated color-selective capabilities on most low observable platforms, including UAVs Enabling Technology: Fiber-delivered laser ablation energy (GLC patents) Color selectivity (GLC patents) Certification: USAF approved Lasertronics color-selective process 2007 USAF approved laser ablation for aircraft in general 2007 Current: USAF AFRL SBIR Ph 1 complete, bid invited for Ph 2 Northrop B2 LO stripping setbacks of 0.25 are typical Boeing UAV stripped result NGC R&D LO sample result A Lasertronics hand-held colorselective workhead

16 Turbine Coating Maintenance Requirement: Remove vitrified silica-based contamination build-up on turbine hot section surfaces and from occluded bleed. air holes. Contamination results from ingested dust, dirt, sand or volcanic ash. Current method: Chemical bath or discard component Motivation: Current process too slow, results are inadequate, bleed air holes not always cleaned, baths are toxic Experience: Lasertronics has demonstrated rapid and complete removal of all CMAS (CaO/MgO/Al 2 O 3 /SiO 2 ) contaminants Enabling Technology: Fiber-delivered laser ablation (GLC patents) Substrate protective closed loop controls (GLC patent pending) CMAS removal by controlled ablation (GLC patent pending) GE F101 Stator Vane (Top untreated, bottom ablated) Current: Planning in process for first large-scale USAF engine reclamation project production order. Partially occluded Bleed-air hole bleed-air hole before after Lasertronics Lasertronics processing processing Photos are 100X SEM views

17 Composite Surface Prep for Coating & Bonding Requirement: Automatically clean, texturize (scuff coat) and activate carbon fiber reinforced plastic for next-generation Boeing aircraft Alternative method: Hand sanding Motivation: Current process too slow, ineffective, damage prone Experience: 2 years of post-stripping adhesion testing with Boeing, prior testing with NGC & LMCO Boeing 787 Enabling Technology: Fiber-delivered laser ablation energy (GLC patents) Composite surface/improved scanning (GLC patent pending) Certification: Repeated OEM feedback that Lasertronics treated coupons outperform all others in terms of pre-bond, pre-paint adhesion and consistency Treated Boeing 787 composite showing undamaged fiber F-35 scarf joint surface - machined results F-35 scarf joint surface - CO 2 process results Lasertronics process results - one pass

18 Automated Rotor Blade Stripping System Requirement: Remove top coat to primer without (fiberglass) blade damage Alternative method: Hand sanding w/high probability of damage Motivation: Current process slow, toxic waste hazard, 10+% damage/scrap rate Experience: Completed first generation system installation in 2009 ARBSS in production since 2010 Enabling Technology: Fiber-delivered laser energy (GLC patents) Color selectivity (GLC patents) Scan control (GLC patent pending) Certification: Sikorsky Aircraft approval on blades/composites US Navy acceptance, 2009 by FRC-East, MCAS Cherry Point, North Carolina Manual blade stripping FRC- East Cherry Point GLC triple-laser robot - mounted workhead Damage from hand sanding Robot design

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22 Toxic Waste Generation Media Blast Solvent Laser Ablation De-painting 1 lb of paint produces 4.1 pounds Solid Waste* pounds Solid Waste* 0.5 pounds Solid Waste** pounds Liquid Waste * Potential Alternative Report for the Portable Handheld Laser Small Area Supplemental Coating Removal System, Prepared for USAF by SAIC, Feb 2001 ** Penn State Applied Research Laboratory, Automated Rotor Blade Stripping System (ARBSS) study for the USN, 2005

23 Other Lasertronics Markets Helicopter rotor blade stripping Building & statuary restoration Radioactive decontamination Ships hull and superstructure stripping Power turbine thermal barrier coat removal Auto body stripping

24 Energetic Depainting Alternatives Favorable Unfavorable Examples Characteristics Femto Flashlamp Nd: YAG Diode pumped Nd: YAG Direct diode or C0 2 pulsed Continuous Wave Pulse Width µsec ,000-10,000 Continuous Pump-pulse Method Beam Delivery Complex Mirrors Electronic + Q-switch Optical Fiber Continuous + Q-switch Optical Fiber Electrical Fibers/Mirrors Continuous Optical Fiber Substrate Temp Rise None Negligible Low Moderate High Coating Color Dependency None Minimal Minimal Moderate Moderate COTS KW-Avg Lab Only < >2 Cost/strip Rate Very High Moderate Lowest Moderate Moderate Lifetime Very Low Low Good (10,000 hrs) Good (10,000 hrs) Good (10,000 hrs)

25 Laser strike irradiance versus pulse width

26 Non-laser Depainting Alternatives

27 De-Painting Rate Comparisons USAF-AFRL Joint Group on Pollution Prevention Study [1] Media Blast Published Rate [Note 2] ft 2 /min Chemical Application ft 2 /min Hand Sanding ft 2 /min Water Jet ft 2 /min GLC 400W Laser 0.80 ft 2 /min [1] Contract Number F D-5615, Delivery Order 0068, CDRL A012, February 2001 [2] All strip rates normalized for to 1 mil thick coatings

28 Depainting Burdened Cost Comparisons Study Aircraft Method Effective Cost * / Sq. Ft. 1 T-45 Trainer Chemical Solvent $ T-38 Trainer Chemical Solvent $ T-38 Trainer Hand Sanding $ T-45 Trainer Plastic Media Blast $ F-4 Fighter Chemical Solvent $ F-4 Fighter Plastic Media Blast $ C-5 Transport Plastic Media Blast $3.50 * Effective Costs - labor, preparation time, damage prevention precautions, power consumption, amortized equipment costs, consumable material costs, and residue disposition costs. All costs based on published sources and normalized to 2006 prices and 1 mil thick coatings. Lasertronics 2014 Burdened Cost $2.10/ square foot Burdened Costs - labor at $100/hr and amortized equipment costs as of Power consumption, consumable material, and residue disposition costs are negligible.