how to save csv file from url through File Download popup window using powershell scrip

Am trying to download csv file from the browser using:

$ie = new-object -com "InternetExplorer.Application"
$wc = New-Object System.Net.WebClient
$source1="https://abc.com"
I see a pop of "File Download" shown with Open Save Cancel Option
I need code for a) How to "Save" this file to a location say c:\-
Every time with current system date because at the moment the script hangs as soon as pop comes and i dont know how to initiate Save button event followed by saving the file to c:\ locaton
Thanks for your help!