In my present scenario I have a Azure VM with managed disk, I would like to know if it is possible to convert the managed disk to unmanaged disk. If this can be done please help me with sufficient details.
You cannot convert a managed disk to an unmanaged disk directly, but as a workaround you can copy the VHD from a managed disk to an unmanaged disk, and use that disk to create a new Virtual Machine.
Please check the references below for more details, these also include guidelines how to copy the VHD and recreate a Virtual Machine.