Hi Maddy,
You will have to create new customized fields for Sample receiving time and sample clearance time.
Then you will have to get pop up for these two fields at the time of result recording, You need to implement user exit for the same, I am not sure about which user exit to use, so verify with help of an ABAPer for below exits.
QEEM0029 User-Exit for Characteristic Overview Subscreen
QEEM0006 User exit: add. functions after closing inspection char
Then, you also need to append QALS_D02 structure so that these two fields will be shown in QA32 report.
Amol.