need help for the questions

The circumstances of failure

A fully loaded container was being lifted when a worker noticed a tear along the joints of the panel.

There was no general collapse, and the cargo remained inside

The container was removed from service and cargo was transported to another one.

Within few weeks similar events (10 before investigation started) occurred scattered around the world

Max weight 30,480kg Length 12.19 m Distance of tear from end 1.25m Panels held together with 48 rivets

OTHER DATA

Major observation?

No deformation of panel

Information received from manufacturer

Rivets were delivered on H2 condition Kept in store until withdrawn anything

between few days to a month.

SEM OF THE RIVETS

Conclusions?

HV test (Vickers Hardness)

Where should the hardness test be performed?

Compression tests on a fully annealed rivet. REDUCTION IN THICKNESS

Anneale d

10% 20% 30% 40% 50% 60% 70% 80% 90%

HV 38.1 53.2 60.3 63.9 67.2 70.7 73.9 75.9 78.8 81.0

Solution treated 2h 800K, quenched and aged for 5 days at 290K

Sample HV Hardness as quenched

HV Hardness after 5 days of ageing at 290K RT

1 56.2 98.5

2 55.3 101

3 52.0 92.7

4 54.4 95.6

Mean 54.5 97.0