Ultra Critical Cleaning: Process and Challenges Dr. Michael Flämmich Vice-President & Head of R&D Fachforum parts2clean 2017

Transcription

1 Ultra Critical Cleaning: Process and Challenges Dr. Michael Flämmich Vice-President & Head of R&D Fachforum parts2clean 2017

2 VACOM at a glance The 25 years ago founded VACOM Vakuum Komponenten & Messtechnik GmbH belongs to the leading european suppliers for vacuum technology and employs currently about 200 people. Production of Precision Components (Turning, Milling, Joining, ) Ultra Critial Cleaning of components as a Service (50k parts / week) Measurement of film-type contamination / organics with VIDAM (100 mg 10 ng) 2

3 Outline Introduction: Types of Contamination & Cleanliness Levels Ultra Critical Cleaning: Process Chain & Results Challenges Standards: VACOM Purity Classes Summary 3

4 Cleanliness Sufficient component cleanliness = sufficiciently low contamination of cleanliness sensitive technical components Cleanliness is absence of contamination Standardisation of technical cleanliness (concerning particles) 2001 => Industrial association Technical Cleanliness TecSa 2004 => VDA19 (VDA = German Association of the Automotive Industry) 2010 => VDA19 part 2 Technical cleanliness in assembly Only recently: Increasing focus on film-type contamination 4

5 Contamination: Particles Examples: Chips, Dust, Micro- and Nanodust, Abrasion, Sources: Mechanical processing (Milling, Turning, Polishing, Grinding), Sandblasting, Storage in environment, Particles in clenaing tank, Lints from cleaning wipes, Packing material, Identification: Visual inspection, UV-A black light check, optical microscope (with image processing), stray ligth scanner, SEM, AFM, Analysis of flushing medium with OPC, Filtering of the flushing medium and gravimetric or microscopic examination 5

6 Contamination: Particles 1e ,1 0,01 0,001 ORK - Partikelanzahl pro cm 2 SCP-Klasse (ISO) - Partikelanzahl/m 2 0,0001 Oberflächenreinheitsklasse ORK (VDI ) Surface Cleanliness by Particle SCP-Klasse (EN ISO Teil 9 ) 1e+08 1e+07 1e+06 1e+05 1e ORK 0.1 bzw. SCP-Klasse 3 0, Partikelgröße in µm 100 SCP-Klasse 2 (ISO) 10 SCP-Klasse 1 (ISO) ORK 1000 bzw. SCP-Klasse 7 (ISO) ORK 100 bzw. SCP-Klasse 6 (ISO) ORK 10 bzw. SCP-Klasse 5 (ISO) ORK 1 bzw. SCP-Klasse 4 (ISO) ORK

7 Contamination: Film-type / Chemical / Organic Examples: Oils / Fats, Cooling lubricants, Proteins, Skin fats, Water, Sources: Mechanical processing (Milling, Turning, ), Pressing, Deep drawing, Residues from detergents, Fingerprints, AMC from the environment, www1.wdr.de Identification : 7

8 Contamination: Film-type / Chemical / Organic Quantitative value: Amount of contamination [g/cm²] or [g] Establishment of appropriate thresholds 12 µg/ cm² Spectral or mass-specific signature of residual contamination Identification of contamination source VIDAM = Measurement of film-type contamination / organics (100mg 10 ng) 8

9 Contamination: unwanted chemical elements Examples: Salts, Heavy metals, Silicons, Sources: Water minerals, false material selection, material selection, Production resources, Storage in environment, Identification: 9

10 Contamination: unwanted chemical elements 10

11 Cleanliness Levels for film-type contamination Pre Cleaning Precision Cleaning Critical Cleaning Ultra Critical Cleaning 100 µg / cm² 5 µg / cm² 500 ng / cm² 5 ng / cm² Rough Vacuum mbar Fine Vacuum mbar High Vacuum mbar Ultra High Vacuum mbar

12 Cleanliness Levels & amount of film-type contamination Reference area: 1 Soccerfield (111m x 90m) cm² = 1E+8 cm² Process Residue / cm² Remaining film per Soccerfield Pre Cleaning 100 µg 1 canister of oil (10 L) Precision Cleaning 5 µg 1 glass of beer (0,5 L) Critical Cleaning 500 ng 2.5 shots (50 ml) Ultra Critical Cleaning 5 ng 10 drops (0,5 ml) 12

13 Process chain Heavy contamination Low contamination Production/ Incoming goods Pre Cleaning/ Precision Cleaning Critical Cleaning Ultra Critical Cleaning Packaging & Transport VIDAM pre VIDAM pre VIDAM fine VIDAM fine 13

14 Process chain: Production Prevent contamination wherever possible Remove coarse dirt immediately Consider cleanability of production aids For instance by means of: Sawing Turning Milling Number of particles > 1µm: > / cm² Total mass of particles: > 1 mg/cm² Surface cleanliness class (ORK): - Film-type contamination: > 1E-3 g/cm² Outgassing rate: > 1E-4 mbar l/s/cm² Particlemeasurement VIDAM- Measurement 14

15 Process chain: Pre Cleaning / Precision Cleaning Number of particles > 1µm: 100 / cm² Total mass of particles : 50 µg/cm² Surface cleanliness class (ORK): 100 Result Oil- and grease free (< 10µg/cm² film-type) Process depends on contamination and parts Requirement for effective Critical Cleaning For instance by means of: Spray Cleaning Ultrasonic Kärcher Film-type contamination : 1E-5 g/cm² Outgassing rate : 1E-4 mbar l/s/cm² Particlemeasurement VIDAM- Measurement 15

16 Process chain: Critical Cleaning Optimal result with pre-cleaned components Number of particles > 1µm: 1 / cm² Total mass of particles : 0.5 µg/cm² Surface cleanliness class (ORK): 1 Process depends on parts and contamination Requirement for effective Ultra Critial Cleaning For instance by means of: Ultrasonic Manually High Pressure Film-type contamination: 5E-7 g/cm² Outgassing rate : 2E-9 mbar l/s/cm² Particlemeasurement VIDAM- Measurement 16

17 Process chain: Ultra Critical Cleaning Effective only for critical cleaned components Process depends on components (material) Particularly effective for film-type / organic For instance by means of: VIDAM_heat Plasma Ozon Number of particles > 1µm: 1 / cm² Total mass of particles : 0.5 µg/cm² Surface cleanliness class (ORK): 1 Film-type contamination: 5E-9 g/cm² Outgassing rate : 4E-10 mbar l/s/cm² Particlemeasurement VIDAM- Measurement 17

18 Process chain: Packaging Preserve parts cleanliness If necessary, moisture barrier, ESD-protection Consider/ prevent recontamination by packaging Examples of primary packing: Barrier foil Aluminum foil Special synthetic Number of particles > 1µm: 1 / cm² Total mass of particles : 0.5 µg/cm² Surface cleanliness class (ORK): 1 Film-type contamination: 5E-9 g/cm² Outgassing rate : 4E-10 mbar l/s/cm² Particlemeasurement VIDAM- Measurement 18

19 Challenges Production/ Incoming goods Pre Cleaning/ Precision Cleaning Critical Cleaning Ultra Critical Cleaning Packaging & Transport VIDAM pre VIDAM pre VIDAM fine VIDAM fine 19

20 Challenge Sufficient initial cleanliness for (Ultra-) Critical Cleaning is necessary Oil- and grease free < 10µg/cm² film-type = Specification Protection of the Process chain by preventing carry-over Desired final cleanliness level needs (production aid) adapted pretreatment Delivery condition FHM1 FHM2 Pre Cleaning: semi-effektive Pre Cleaning: effective 650 µg/ cm² 143 µg/ cm² 5,1 µg/ cm² 20

21 Challenge Effective cleaning procedures for Ultra Critical Cleaning are scare good Vacuum bakeout: highly effective for organic contamination Integral removal of films / organic Films / organic residue < 5ng/cm² achievable Precision Cleaning Critical Cleaning Ultra Critical Cleaning (VIDAM_heat) 1,7 µg/ cm² 12 ng/ cm² 1,2 ng/ cm² 21

22 Challenge Prevent recontamination of ultra-clean components by primary packing Material of primary packing often contains plastic / organics Examination of packaging & identification of recontamination sources Prevent organic recontamination of component surfaces Before Packaging & Transport After Packaging & Transport Packing Material #1 #2 22

23 VACOM Purity Classes Guaranteed Cleaning results = guaranteed parts cleanliness Concerning film-type contamination, particles, unwanted chemical elements 23

24 Summary What s beyond Critical Cleaning?! Ultra Critical Cleaning ORK 1 SCP-Class 4 Organics 5 ng/cm² Absence / Limits of specific chem elements Challenge: control the entire process chain VACOM: Ultra Critical Cleaning as a service with guaranteed parts cleanliness 24

25 Halle 5, Stand D40 VACOM Vakuum Komponenten & Messtechnik GmbH In den Brückenäckern Großlöbichau/Germany