Abstract: A rack (100) configured for holding workpieces is provided. The rack includes a base (10) and a plurality of fixtures (20). The base includes two lateral frames (14) and a fixing frame (16) fitted between the two lateral frames. Each of the lateral frames includes a first stopper (147) and a second stopper (148) mounted thereon. The fixing frame has two fixing poles (164) parallel to the two lateral frames. Each of the two fixing poles has a plurality of latching means (166) mounted thereon in line. The plurality of fixtures rotatably engage with the latching means of the fixing frame and are fitted between the first stopper and the second stopper.

Abstract: A printing method comprises: providing a metal housing; printing a first ink coating on the metal housing and drying the first ink coating at a temperature of about 100-150° C. for about 15-25 minutes, the first ink coating including epoxy resin; printing a second ink coating on the first ink coating and drying the second ink coating at a temperature of about 100-150° C. for about 15-25 minutes, the second ink coating including epoxy resin; and printing a third ink coating on the second ink coating and drying the third ink coating at a temperature of about 100-150° C. for about 60-120 minutes, the third ink coating including epoxy resin.

Abstract: A rack (100) configured for holding workpieces is provided. The rack includes a base (10) and a plurality of fixtures (20). The base includes two lateral frames (14) and a fixing frame (16) fitted between the two lateral frames. Each of the lateral frames includes a first stopper (147) and a second stopper (148) mounted thereon. The fixing frame has two fixing poles (164) parallel to the two lateral frames. Each of the two fixing poles has a plurality of latching means (166) mounted thereon in line. The plurality of fixtures rotatably engage with the latching means of the fixing frame and are fitted between the first stopper and the second stopper.

Abstract: A rack (300) configured for holding workpieces (50) includes a base unit (30) and a cover unit (40). The base unit includes a plurality of holding members (31). Each holding member includes two parallel holding boards (311, 313) cooperating with each other to hold the workpieces, each holding board defines a plurality of gaps (312, 314) corresponding to the workpieces therein. The cover unit covers on the base unit.

Abstract: A method for cleaning aluminum article includes steps of first water washing for a aluminum article; cleaning the aluminum article with mildly alkaline solution which including phosphate, carbonate and silicate; and second water washing for the aluminum article.

Abstract: A surface treatment process for a metal article includes the following steps. Firstly, a metal article, made of at least one of copper and an alloy thereof, is provided. Secondly, a surface of the metal article is degreased. Thirdly, the surface of the metal article is activated in an acid solution. Finally, the surface of the metal article is deactivated by submersion in an antioxidant agent.

Abstract: A cleaning agent for metal parts (e.g., steel articles) includes sodium hydroxide in an approximate amount of 15 wt % (percent by weight) to 25 wt %, sodium tripolyphosphate in an approximate amount of 6 wt % to 9 wt %, sodium metasilicate in an approximate amount of 48 wt % to 51 wt %, sodium dodecyl benzene sulfonate in an approximate amount of 2 wt % to 5 wt %, sodium carbonate in an approximate amount of 8 wt % to 11 wt %, and alkylphenol polyoxyethylene ether in an approximate amount of 1 wt % to 4 wt %.

Abstract: A surface treatment process for a metal article includes the following steps. Firstly, a metal article, made of at least one of copper and an alloy thereof, is provided. Secondly, a surface of the metal article is degreased. Thirdly, the surface of the metal article is activated in an acid solution. Finally, the surface of the metal article is deactivated by submersion in an antioxidant agent.

Abstract: A surface cleaner for metal parts (e.g., steel articles) is an aqueous solution, which contains a component of phosphoric acid (H3PO4) from approximately 15 wt % (percent by weight) to approximately 25 wt %, a measurable component of ferrous ions (Fe2+) less than about 5 wt %, and water. Due to the beneficial composition of the surface cleaner, contaminants (e.g., oils, lubrications, and rust) can easily be removed from the surfaces of the metal parts, especially steel parts.