Weld observations

WELD OBSERVATIONS

Presented by: De Carlo Livio

Supervisor: Scheubel MaudSection: EN/MME-MM

Type: Hostaphan RNK 2600 Hostaphan RNK 2600 Hostaphan RNK 2600From: Sefar Sefar JINRDate: September 2010 December 2010 January 2011Samples: 6 2 (S1=#89 & S2=#89_2) 2 (R1=#047 & R2=#002)

Observations with stereomicroscope○ Both sides (coated and chemically treated)

and cross section Observations with optical microscope

○ Polished cross section Tensile tests

○ 10*31 mm

Stereomicroscope observations

• Length: 0,9 mm• Thickness: 60 to 70 μm• Critical section: - Thickness: 30 μm to 45 μm - Length: 110 μm to 170 μm

• Length: 0,3 mm• Thickness: 60 to 70 μm• Extremities not correctly welded

4 samples presented a weld like: 2 samples presented a weld like:

Type 1 Type 2

6 samples from Sefar September 2 samples from Sefar December Type 3

2 samples from JINR January Length: 0,8 to 0,9 mm Thickness: 55 to 60 μm

Length: 0,9 mm Thickness: 64 μm Length: 0,6 mm Thickness 50 to 90 μm

Tensile tests

54

32

1

1bis

6 samples from Sefar September

S1R2

S2

R1

2 samples from Sefar December and 2 samples from JINR January

Tensile test results 6 samples from Sefar September

2 samples from Sefar December and 2 samples from JINR January

Hostaphan RNK 2600 welded and treated (36 µm)

Type Tensile strength (MPa)

Sample S1 Type 3 127,5Sample S2 Type 3 127,6Sample R1 Type 3 124,2Sample R2 Type 3 132,6

Hostaphan RNK 2600 welded and treated (36 µm)

Type Tensile strength (MPa)

Sample 1 Type 1 120,7 Sample 1bis Type 1 127,2 Sample 2 Type 2 109,6 Sample 3 Type 2 112,4 Sample 4 Type 1 107,2 Sample 5 Type 1 105.4

Stereomicroscope observations after tensile test

Unsticking of the two extremities

6 samples from Sefar September

Type 1

Failure in the critical section

Type 2

Stereomicroscope observations after tensile test

2 samples from Sefar DecemberType 2Type 3

2 samples from JINR January

S1: Failure in the weld

S2: Failure outside the weld but apparition of a crack

Elongation

R1: Failure outside the weld

R2: Failure outside the weld but apparition of a crack

Elongation

Optical microscope observations 6 samples from Sefar September 2 samples from Sefar December

2 samples from JINR January Melted area not visible

Optical microscope observations Melted area measurements

SEFAR2

Samples Bef. t.t (%) Aft t.t (%)

Sefar 1 42,6 36,7

Sefar 2 52,4 47,4

Dubna 1 49,0 49,0

Dubna 2 33,3 30,6

Optical microscope observations Length measurements

SEFAR1

DUBNA2

Samples Bef. t.t (μm)

Aft t.t (μm)

Elongation(µm)

Sefar 1 870 970 100

Sefar 2 860 910 50

Dubna 1 850 860 10

Dubna 2 550 600 50

Optical microscope observations Thickness measurements

DUBNA1

Sefar 1: Failure in the weld

Sefar 2: No failure but apparition of an elongation

Comment: No a significant reduction of thickness in the weld, failure happens suddenly

Comment: Slight reduction but not significant

JINR 1: No failure and no elongation in the weld

Comment: The reduction of section is more visible

JINR 2: No failure but apparition of an elongation

Comment:No significant reduction

Optical microscope observation Width outside the weld measurements

DUBNA1

Thickness (µm) Section 1 Section 2 Section 3 Section 4 Section 5 Section 6Point 1 36 36 36 36 36 36Point 2 37 36 37 36Point 3 37Point 4 37

Comment:

Thickness of 36 to 37 µm => No measurable reduction lower than 1 µm

Conclusions

Improvement in weld formation by Sefar (September to December) and JINR

JINR weld has the same behavior at the failure than Sefar December

1 / 2 of weld Sefar December resist to the tensile test

2 / 2 of weld JINR resist to the tensile test All results should be confirm by next

observations

Next step Observations of four samples from Sefar

December 2010/ Sefar January 2011/ JINR to be delivered

Optical analyze

Optical analyze

Tensile test

Sections comparison

4X

Thank you for your attention

Tensile test results:

Hostaphan RNK 2600 welded and treated (36 µm)

Type

Tensile strength (MPa)

Elongation at rupture (%)

Hostaphan RNK 2600 no welded and without deposit (36 µm)

Sample 1 Type 1 120,67 7,66

Sample 1bis Type 1 127,19 8,96

Sample 2 Type 2 109,54 / Tensile strength(MPa) 260-280

Sample 3 Type 2 112,36 /

Sample 4 Type 1 107,19 3,89 Elongation at rupture 25-40 %

Sample 5 Type 1 105.37 2,99

6 samples from Sefar September

2 samples from Sefar December and 2 samples from Dubna January Hostaphan RNK 2600 welded and treated (36 µm)

Tensile strength (MPa)

Elongation at rupture (%)

Sample S1 127,49 12,35 Sample S2 127,57 10,65 Sample R1 124,21 5,1 Sample R2 132,61 9,48