02 wiresemcern feb02

SEM Analysis of Wire from Aging Test #5 : 

SEM Analysis of Wire from Aging Test #5 Jack Fowler

Module Test Layout : 

Module Test Layout

Wire Samples Analyzed: 

Wire Samples Analyzed Xe-CO2 gas volume Wire 11 – Production wire with glass encapsulated joint Wire 12 – Production wire with glass encapsulated joint Wire 14 – Production wire with glass joint Xe-CF4-CO2 gas volume Wire 16 – Production wire with glass encapsulated joint Wire 18 - Production wire with glass encapsulated joint Wire 20 – Pre Series 1 (.3 to .4 m) with PEEK joint Wire 24 - Production wire with glass encapsulated joint Wire analysis Performed at Analytical Instrumentation Facility at North Carolina State University

Wire 11 Segment 1: 

Wire 11 Segment 1 Very small pores Fine scratches No deposits

Wire 11 Segment 3: 

Wire 11 Segment 3 Very small pores Fine scratches No deposits

Wire 11 Segment 4: 

Wire 11 Segment 4 Very small pores Fine scratches No deposits

Wire 11 Segment 5: 

Wire 11 Segment 5 Very small pores More scratches, these are probably made during production No deposits

Wire 11 Segment 5 Close up: 

Wire 11 Segment 5 Close up Medium size pores ~0.25 m, more densely populated than upstream No deposits Grain boundary very defined

Wire 12 Segment 5: 

Wire 12 Segment 5 Very small pores One large scratch that does not appear to have compromised the wire No deposits

Wire 12 Segment 6: 

Wire 12 Segment 6 Very small pores Many scratches, probably made in production No deposits

Wire 12 Segment 6 Close Up: 

Wire 12 Segment 6 Close Up Very small pores Fine scratches, wire has not been compromised No deposits

Wire 12 Segment 7: 

Wire 12 Segment 7 Very small pores Few scratches No deposits Some surface contamination

Wire 12 Segment 7 Close Up: 

Wire 12 Segment 7 Close Up Very small pores Small scratch No deposits Defect in gold plating does not appear to have enlarged

Wire 24 Segment 1: 

Wire 24 Segment 1 Very small pores One large scratch along top surface No deposits

Wire 24 Segment 2: 

Wire 24 Segment 2 Very small pores One scratch along center, appears the same as the rest of the surface Some small white deposits

Wire 24 Segment 3: 

Wire 24 Segment 3 Many pores of all sizes Surface is covered with deposits, analysis indicates they are Au

Wire 24 Segment 3 Close Up: 

Wire 24 Segment 3 Close Up Note how the deposits seem to be in clusters Again the elemental analysis indicates only Au

Wire 24 Segment 4 in CWS: 

Wire 24 Segment 4 in CWS Wire appears very clean and undamaged

Wire 24 Segment 4 beside CWS: 

Wire 24 Segment 4 beside CWS Wire surface appears smooth Many large white deposits. These show up as Au, C, O and F.

Wire 24 Segment 4 Surface Analysis: 

Wire 24 Segment 4 Surface Analysis This is the elemental analysis of the dark areas around the deposits Note the C and F peaks. The C is greater than the F.

Wire 24 Segment 4 Surface Analysis: 

Wire 24 Segment 4 Surface Analysis This is a elemental analysis of the white deposits Note the C and F peaks have become equal

Wire 24 Segment 4 Close Up: 

Wire 24 Segment 4 Close Up Here is a close up of the gold damage

Wire 24 Segment 4 Epoxy: 

Wire 24 Segment 4 Epoxy This shows the region where the epoxy meets the wire. The epoxy is covered with deposits

Wire 24 Segment 4 Epoxy Surface Analysis: 

Wire 24 Segment 4 Epoxy Surface Analysis Note the large F and C peaks on the surface of the Epoxy. Note also the absence of Au

Wire 24 Segment 5: 

Wire 24 Segment 5 Many pores of all sizes Surface is covered with deposits, the analysis indicated Au Also note dark appearance of surface

Wire 24 Segment 5 Close Up: 

Wire 24 Segment 5 Close Up Many pores of all sizes Note the grain boundaries have lost their definition

Wire 24 Segment 6: 

Wire 24 Segment 6 Many pores of all sizes Surface is covered with deposits, Au only

Wire 16 Segment 6: 

Wire 16 Segment 6 Note that the large scratch does not appear to have been damaged more than the rest of the surface

Wire 24 Segment 7: 

Wire 24 Segment 7 Many pores of all sizes Surface deposits have drastically reduced

Wire 24 Segment 7 Close Up: 

Wire 24 Segment 7 Close Up Many pores of all sizes Note the pores occur on the grain boundaries Surface deposits have drastically reduced

Wire 20 Segment 1: 

Wire 20 Segment 1 Surface appears normal Light scratches No deposits

Wire 20 Segment 3: 

Wire 20 Segment 3 Wire is still in good condition Fine pores No scratches No deposits

Wire 20 Segment 4: 

Wire 20 Segment 4 Heavy damage of gold plating Large deposits Analysis indicates the deposits are mainly Au

Wire 20 Segment 4: 

Wire 20 Segment 4 Heavy damage to wire

Wire 20 Segment 4: 

Wire 20 Segment 4 Wire coming out of wire joint Surface of the wire shows heavy deposits The PEEK appears undamaged

Wire 20 Segment 5: 

Wire 20 Segment 5 Many pores Heavy deposits These deposits contained Au and W

Summary: 

Summary It is clear that the wire is damaged Xe-CO2 wire only exhibit small pores on surface Xe-CF4-CO2 wires show heavy damage, both Au removal and deposits It appears that the damage increases in the high radiation areas and as you move downstream in the straw Thicker Au plating protects the wire longer There is fluorine detected on the surface of the wire We detected no silicon on the surface

To Do: 

To Do Inspect incoming wire for pores We have never seen these pores on unused wire Confirmation of the test results This should be done when IU gets their test results Evaluate the possibility of water being trapped on surface, that may accelerate the damage Evaluate differences from earlier tests

Thin Plating Comparison: 

Thin Plating Comparison

What are the Deposits? Si or Au: 

What are the Deposits? Si or Au

Surface Damage: 

Surface Damage