Reducing base deck porosity

Abstract

A method for making a hard disk drive is disclosed. The method includes forming a base deck comprising an aluminum alloy via vacuum casting. The method further includes subjecting the base deck to hot isostatic pressing. The method further includes welding a cover to the base deck.

I claim: 
     
         1 . A method for making a hard disk drive, the method comprising:
 forming a base deck comprising an aluminum alloy via vacuum casting;   subjecting the base deck to hot isostatic pressing; and   welding a cover to the base deck.   
     
     
         2 . The method of  claim 1 , wherein the subjecting the base deck to hot isostatic pressing includes:
 placing the base deck in a chamber;   raising a chamber temperature of the chamber to substantially near a solidus temperature of the base deck;   raising a chamber pressure of the chamber to a target pressure; and   holding the chamber temperature and the chamber pressure for a predetermined time period.   
     
     
         3 . The method of  claim 1 , wherein the subjecting the base deck to hot isostatic pressing includes reducing the porosity of the base deck from a first porosity to a second porosity. 
     
     
         4 . The method of  claim 3 , wherein the second porosity is 50-95% less porous than the first porosity. 
     
     
         5 . The method of  claim 3 , wherein the first porosity and the second porosity is measured as a total average porosity of the base deck. 
     
     
         6 . The method of  claim 3 , wherein the first porosity and the second porosity is measured as a total average porosity of a volume including one or more machined sections of the base deck. 
     
     
         7 . The method of  claim 1 , wherein the welding a cover to the base deck includes friction stir welding the cover to the base deck. 
     
     
         8 . The method of  claim 1 , further includes at least partially filling the hard disk drive with helium. 
     
     
         9 . The method of  claim 1 , further includes subjecting the base deck to an impregnation process. 
     
     
         10 . The method of  claim 9 , wherein the subjecting the base deck to the impregnation process includes introducing an impregnating agent into surface-connected porosity of the base deck. 
     
     
         11 . The method of  claim 9 , wherein the subjecting the base deck to the impregnation process is performed after the subjecting the base deck to hot isostatic pressing. 
     
     
         12 . A base deck for a hard disk drive, the base deck comprising:
 a base plate and sidewalls extending therefrom and integral with the base plate, both the base plate and the sidewalls comprising a vacuum-casted aluminum alloy having a porosity that is reduced by 50-95%.   
     
     
         13 . The base deck of  claim 12 , further including an impregnating agent at least partially filling the aluminum alloy's surface-connected porosity. 
     
     
         14 . The base deck of  claim 12 , wherein the aluminum alloy is selected from a group consisting of ADC12, A380, and A383. 
     
     
         15 . The base deck of  claim 12 , wherein the base plate and the sidewalls are hot isostatically pressed. 
     
     
         16 . The base deck of  claim 12 , wherein the base deck is coupled to a cover to create a sealed enclosure. 
     
     
         17 . The base deck of  claim 16 , wherein the cover is welded to the base deck. 
     
     
         18 . The base deck of  claim 17 , wherein the sealed enclosure is at least partially filled with helium. 
     
     
         19 . The base deck of  claim 12 , wherein the porosity is measured as a total average porosity of the base deck. 
     
     
         20 . An apparatus for subjecting a base deck to hot isostatic pressing, the apparatus comprises:
 a chamber configured to receive a base deck;   a heating module configured to raise a chamber temperature of the chamber to substantially near a solidus temperature of the base deck; and   a pressurizing module configured to raise a chamber pressure of the chamber to a target pressure;   wherein the apparatus is configured to hold the chamber temperature and the chamber pressure for a predetermined time period.