Abstract:
A device housing providing a sensation of touch similar to that of jade is made of a material including quartz, clay mineral and a polymer composition containing calcium-magnesium. The clay mineral includes elemental Zn, aluminum oxide, calcium oxide, magnesium oxide, barium oxide, silicon oxide, and titanium oxide. The polymer composition containing calcium-magnesium comprises iron (III) oxide, iron (II, III) oxide, calcium carbonate, and calcium silicate. A method for manufacturing the device housing is also provided.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The exemplary disclosure generally relates to a device housing and a method for manufacturing the device housing. 
         [0003]    2. Description of Related Art 
         [0004]    Metal, plastic and glass are widely used to form housings of electronic devices. However, these common housing materials have disadvantages such as low erosion resistance and fragility and cannot provide the smoothness and tactile sensations that jade can. 
         [0005]    Therefore, there is room for improvement within the art. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0006]    Many aspects of the device housing can be better understood with reference to the following FIGURE. The components in the figures are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the device housing. 
           [0007]    The FIGURE is a cross-section of a device housing according to an exemplary embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0008]    The FIGURE shows a device housing  10  according to an exemplary embodiment. The device housing  10  may be a housing of a mobile phone, a personal digital assistant, a notebook computer, an MP3 player, a GPS navigator, a bluetooth headset, a digital camera, a sound box, etc. 
         [0009]    The device housing  10  is made of a material substantially comprising quartz, clay mineral, and a polymer composition containing calcium-magnesium. The device housing  10  further contains a doping agent such as carbide, nickel oxide, and lead oxide. In the device housing  10 , the mass percentage of the quartz is about 51% to about 62%, the mass percentage of the clay mineral is about 27% to about 34%, the mass percentage of the polymer composition containing calcium-magnesium is about 8% to about 10%, and the mass percentage of the doping agent is about 3% to about 5%. 
         [0010]    The clay mineral contains kaolinite, montmorillonite, calcite, mica, and/or illite. 
         [0011]    The clay mineral contains elemental zinc (Zn) and oxides such as aluminum oxide (Al 2 O 3 ), calcium oxide (CaO), magnesium oxide (MgO), barium oxide (Ba 2 O 3 ), silicon oxide (SiO 2 ), and titanium oxide (TiO 2 ). The polymer composition containing calcium-magnesium contains iron (III) oxide (Fe 2 O 3 ), iron (II, III) oxide (Fe 3 O 4 ), calcium carbonate (CaCO 3 ), and calcium silicate (CaSiO 4 ). 
         [0012]    A method for manufacturing the device housing  10  may include the following steps: 
         [0013]    (1) The material for making the device housing  10  is provided. The material is in powder form and has a grain size of about 0.4 mm to about 0.1 mm. 
         [0014]    (2) A molding feedstock is provided. 
         [0015]    The material, a binder, and a plasticizer are mixed together to produce a mixture. In the mixture, the volume ratio of the material, binder, and plasticizer is about (42-47): (35-50):(3-8). The mixture is agitated in a mixer (not shown) at a temperature of about 140 degrees Celsius (° C.) to 180° C. for about 60 min to about 150 min to produce a cylindrical molding feedstock. The binder includes polyethylene (PE) and polypropylene (PP). The plasticizer is dibutylphthalate (DBP). The length of the molding feedstock is about 4 mm to 7 mm. The diameter of the molding feedstock is about 2 mm to 3 mm. 
         [0016]    (3) A green body is formed by powder injection molding. 
         [0017]    A mold (not shown) is provided. The molding feedstock is heated to about 150° C.-170° C. and then injected into the mold under a pressure of about 120 MPa to about 180 MPa. After the injection process, the mold is maintained at a pressure of about 200 MPa to about 300 MPa for about 20 min to about 50 min. 
         [0018]    (4) The green body is heated to degrease. 
         [0019]    The green body is positioned in a degreasing furnace (not shown). The internal temperature of the degreasing furnace is heated to about 850° C. by the following steps: first, the internal temperature of the furnace is heated to about 150° C. at a rate of about 25° C./h to about 37° C./h; second, the internal temperature of the degreasing furnace is heated to about 400° C. at a rate of about 3.8° C./h to about 6.3° C./h; third, the internal temperature of the degreasing furnace is heated to about 500° C. at a rate of about 6.6° C./h to about 10° C./h; fourth, the internal temperature of the degreasing furnace is heated to about 850° C. at a rate of about 29.2° C./h to about 50° C./h. During the degreasing process, the binder and the plasticizer contained in the green body are melted, decomposed and removed. After the degreasing process, the green body is naturally cooled to room temperature. 
         [0020]    (5) The green body is sintered. 
         [0021]    The green body is positioned in a sintering furnace (not shown). The interior of the sintering furnace is heated to about 1250° C. by the following steps: first, the internal temperature of the sintering furnace is heated to about 600° C. at a rate of about 4° C./h to about 6° C./h; second, the internal temperature of the sintering furnace is heated to about 800° C. at a rate of about 2° C./h to about 4° C./h; third, the internal temperature of the sintering furnace is heated to about 1250° C. at a rate of about 0.8° C./h to about 1.2° C./h. 
         [0022]    After that, the internal temperature of the sintering furnace is cooled to room temperature at a rate of about 3.7° C./h to about 6° C./h. 
         [0023]    (6) The green body is milled by a computer numerical control or cut by laser beam to produce the device housing  10  with a desired shape. 
         [0024]    (7) The device housing  10  is ground or polished. 
         [0025]    (8) The device housing  10  is cleaned by the following steps: first, the device housing  10  is washed with a weak acid solution having a pH value of about 5 for about 5 min to 15 min to remove any alkaline doping agent on the surface; second, the device housing  10  is washed with a weak alkali solution having a pH of about 9 for about 5 min to 15 min to remove any acid doping agent on the surface; third, the device housing  10  is washed with an alcohol or acetone for about 5 min to 15 min to remove any organic doping agent on the surface; fourth, the device housing  10  is washed with pure water and then dried at a temperature of about 60° C.-80° C. for about 40 min to about 80 min. In the embodiment, the weak acid is a hydrochloric acid solution, and the weak alkali is a sodium hydroxide solution. 
         [0026]    The device housing  10  manufactured by this method provides users with the same tactile sensations as given by jade. Further, the device housing  10  has excellent corrosion resistance and aging resistance. In addition, the device housing  10  can form any three-dimensional structure easily since it is formed by molding. 
         [0027]    It is to be understood, however, that even though numerous characteristics and advantages of the exemplary disclosure have been set forth in the foregoing description, together with details of the system and function of the disclosure, the disclosure is illustrative only, and changes may be made in detail, especially in the matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.