1、Standard Test Procedure for Measuring the Dissolution of Aluminum HardenersTP-2Standard Test Procedure for Measuringthe Dissolution of Aluminum HardenersNo warranty or guarantee of any kind, expressed or implied, by the Aluminum Association or its member companies accompanies this information. Accor
2、dingly, the Aluminum Association and its member companies assume no responsibility or liability for their use whether based on warranty, contract, negligence, strict liability product liability, or otherwise.The use by any member or nonmember of this test procedure is purely voluntary. The Associati
3、ons publication of this test procedure does not in any respect prevent or restrict any member or nonmember from manufacturing or supplying products tested under this or any other test procedure.All Aluminum Association published standards, data, specifications and other material are reviewed at leas
4、t every five years and revised, reaffirmed or withdrawn. Users are ad vised to contact the Aluminum Association to ascertain whether the information in this publication has been superseded in the interim between publication and proposed use.Standard Test Procedure for Measuring The Dissolution of Al
5、uminum Hardeners1. ScopeThe Aluminum Association dissolution test procedure can be used to determine the suitability of an aluminum hardener product for alloying purposes. The test procedure describes a method for measuring dissolution time and recovery of the hardener element under standardized con
6、ditions. This method is not intended to predict dissolution rate or recovery under production conditions in commercial opera-tions.2. Applicable Specifications and Registration Records The following specifica-tions or registration records (the issue in effect on date of material purchase) form a par
7、t of the test procedure:2.1 The Aluminum Association Registration Record, “International Designations and Chemical Composition Limits for Aluminum Hardeners” (Gray Sheets).2.2 OSHA - 1910.1200 Hazard Communication Standard.2.3 ASTM Standard E34, Test Methods for Chemical Analysis of Aluminum and Alu
8、minum-Base Alloys, and ASTM E88, Practice for Sampling Nonferrous Metals and Alloys in Cast Form for Determination of Chemical Composition.2.4 ASM Handbook, Volume 9, Metallography and Microstructures, 2004, p. 771.2.5 ASTM B215, Standard Methods for Sampling Finished Lots of Metal Powders.2.6 ASTM
9、E716, Standard Practice for Sampling Aluminum and Aluminum Alloys for Spectrochemical Analyses.3. Sample Location, Sample Frequency and Lot Definition3.1 Ingot - Each heat of material shall be considered a lot. An ingot, selected randomly from a heat, may be considered representative of the lot.3.2
10、Briquet - A lot is defined as a finite quantity produced under uniform condi-tions and should be clearly identified on material packaging. A shipment may contain more than one lot. Sample selection for chemical analysis shall be on a one lot basis and shall consist of one briquet pulled from each of
11、 three and not more than five randomly-selected shipping containers. Combined, these briquets are termed a “gross lot sample” and will be the basis for a discreet analytical determination. Multiple “gross lot samples” shall be pulled if multiple chemical determinations are required. Sample selection
12、 for dissolu-tion rate testing shall be completed in a similar manner, however, the total number of briquets required is to be based on addition level, and test bath weight. This sample should be held separate from analytical sample(s).3.3 Canned Hardeners - A lot is defined as a finite quantity, al
13、l of which is produced under the same conditions. A single can shall be pulled from a randomly-selected product container.3.4 Powder - A lot is defined as a finite quantity, all of which is produced under the same conditions. A powder sample of the required weight shall be taken from a randomly-sele
14、cted product container using approved sample cutting techniques.4. Sample Preparation4.1 Chemical Analysis - The randomly-selected samples shall be prepared as follows:4.1.1 Ingot - The sample for chemical analysis shall be comprised of dry drillings. The drillings shall be obtained from five (5) po
15、sitions of the ingot, diagonally located (Figure 1), and shall include approximate equal weight of drill chips from top, middle and bottom for each sample point of the ingot. The drillings shall be mixed to form the sample4.1.2 Briquet - The chemical analysis sample(s) for briquetted hardeners shall
16、 consist of ground material taken from the “gross lot sample” described in Section 3.2. The entire “gross lot sample” must be crushed with a mortar and pestle or mechanical pulverizer, taking care to minimize contamina-tion or carryover. The resulting powder must freely pass through an 8 mesh (2.36m
17、m) screen. The entire sample is then blended in a suitably-sized blender. It is recommended that a suitably-volatile-blending-aid addition be made during the blending step. The blended gross sample is then passed through a sample splitter to obtain four subsamples, 25 to 50 grams weight each. If a b
18、lending aid was added, it should be dried from the final subsamples before analysis. Three subsamples are analyzed. The final lot composition estimate is the average of the three separate analytical values.4.1.3 Powder - The required amount of powder shall be obtained from the sample using approved
19、sample cutting techniques, per ASTM B215.4.2 Dissolution Rate - For determination of dissolution rate and recovery and metal-lographic examination, samples shall be prepared as follows:4.2.1 Ingot - The randomly-selected ingot shall represent the heat. The sample for the dissolution test shall consi
20、st of one piece of the required weight, including top and bottom surface from the center position of the ingot.4.2.2 Briquet - The “dissolution sample” collected as per Section 3.2 shall represent the production lot. It should consist of the required total briquet weight to meet addition level requi
21、rements for the involved test bath weight. Use of partial briquets should be avoided.4.2.3 Powder and Cans - A randomly-selected powder sample or split sample, from the can, shall represent the batch or lot.5. Chemical Composition5.1 Procedure - The sample prepared in accordance with Section 4.1 sha
22、ll be analyzed in accordance with ASTM Standard E34, Test Methods for Chemical Analysis of Aluminum and Aluminum-Base Alloys, and ASTM E88, Practice for Sampling Nonferrous Metals and Alloys in Cast Form for Determination of Chemical Composition.5.2 Requirements - The hardeners, if registered, shall
23、 conform to the chemical composition limits shown in The Aluminum Associations Registration Record “International Designations and Chemical Composition Limits for Aluminum Hardeners” or, if not registered, the hardener composition shall be as agreed by the supplier and purchaser.6. Dissolution Test
24、Procedure Description - This standard test procedure is applicable for determining the dissolution rate of aluminum master alloys, or additives, in 99.7% aluminum and the recovery of the alloying element.6.1 Dissolution Test Supplies and Equipment6.1.1 Supply of 99.7% (P1020A) pure virgin aluminum w
25、ith the following limits on impurities.Silicon 0.10 maxIron 0.20 maxOthers, each 0.03Total 0.10Aluminum BALANCEOther aluminum purity levels, mutually acceptable to the supplier and purchaser, may be used.6.1.2 Electric resistance furnace capable of maintaining 1382F 10F (750C 5C), and large enough t
26、o contain the required size crucible (Section 6.1.3).6.1.3 A crucible of material, inert to liquid aluminum or one with a suitable coating to render it inert, such as silicon carbide, clay-bonded graphite with Terrepain 55M coating or cast iron with Dykote (a Foseco product) coating. Alternative coa
27、tings, found to be equivalent, may be used. The size of the crucible shall be adequate to hold a heat large enough to provide the required number and size of samples.6.1.4 Calibrated and certified thermocouple and controller indicator capable of controlling and measuring temperature up to 1392F (755
28、C).6.1.5 One appropriately-sized sampling ladle.6.1.6 Graphite melt skimmer with flat paddle surface.6.1.7 Clean aluminum plate.6.1.8 One standard, Type B, ASTM, E716, center-pour mushroom sample mold.6.1.9 Sixty-minute timer.6.1.10 Graphite stirring rod, 1-inch diameter x 24” long (25.4 mm diameter
29、 x 609 mm long).6.1.11 Argon supply and appropriate tubes for fluxing. 6.1.12 Spectrochemical analysis equipment.6.1.13 Lathe and tools for machining spectrochemical disc sample.6.1.14 Magnaflux Digital Conductivity Meter, Model FM140, or equivalent.6.1.15 Notebook.6.1.16 Personal protective clothin
30、g and face shield. 6.2 Procedure for Dissolution Test6.2.1 Weigh aluminum (Section 6.1.1) to provide the desired heat size, place in appropriately-sized, clean, skull-free crucible (Section 6.1.3), and record weight of aluminum in notebook.6.2.2 Heat the aluminum to an appropriate temperature and st
31、abilize so that after addition of hardener, aluminum temperature shall be:6.2.2.1 1337F 10F (725 5C) for products to be used in a remelt facility.6.2.2.2 1382F 10F (750 5C) for products to be used in a smelter facility.6.2.2.3 Other test temperatures may be used, subject to mutual agreement by the s
32、upplier and the purchaser.6.2.3 Flux melt with dry Argon flow rate of 4 cubic feet per hour for 10 minutes.6.2.4 Skim the dross from the aluminum surface, deposit skim on clean aluminum plate or cast into suitable mold. When cooled to ambient tem-perature, weigh dross and record weight.6.2.5 Take an
33、 initial blank sample for chemical analysis.6.2.5.1 Float the sample ladle on surface of the metal until it reaches temperature of the melt. If this chills the melt below the desired temperature, then heat ladle in a furnace.6.2.5.2 Tilt the sample ladle and fill with molten metal.6.2.5.3 Remove sam
34、ple ladle and pour contents into the preheated (350F 177C) mushroom sample mold, return excess metal to crucible.6.2.5.4 After sample has solidified, remove from mold and number sample “0”.6.3 Nominal target composition for elements that are found in commercial alloys:Bismuth 0.10% or 0.50%Boron 0.0
35、2%Chromium 0.25%Copper 0.05% or 5.0%Iron 0.50% or 1.0%Lead 0.50%Magnesium 0.50% or 5.0%Manganese 1.2%Nickel 0.7%Silicon 1.0% or 12.0%Strontium 0.02%Titanium 0.05% or 0.20%Vanadium 0.08%Zirconium 0.12%NOTE: Refer to OSHA-1910.1200 Hazard Communications Standard6.4 Based upon the remaining heat size,
36、calculate the quantity of hardener product required (equation below). Weigh hardener to be added, record calculation and weights in notebook.WE WEHD AH=where:WH= Weight of hardener alloy to be added, lbs (kg)ED= Element content desired in melt, percentEH= Element content of hardener, percent (actual
37、 content reported by supplier or as determined by the user)WA= Weight of aluminum melt, lbs (kg)6.5 Add the weighed hardener to the molten aluminum. Materials less dense than the aluminum should be held below the aluminum surface using coated steel or graphite tools.6.6 For alloy hardeners, stir the
38、 melt vigorously for 30 seconds immediately before the first sample is taken and then for 10 seconds immediately before each additional sample.6.6.1 Samples (Section 6.2.5) shall be taken as follows:(a) For first 10 minutes at 1-minute intervals.(b) For next 50 minutes at 10-minute intervals.(c) Ski
39、m dross from aluminum surface, cool, weigh, and record as in Section 6.2.4.6.7 For briquets, do not stir for five minutes after addition.6.7.1 Samples (Section 6.2.5) shall be taken as follows:(a) After addition,2 minutes 20 minutes5 minutes 30 minutes10 minutes Final Sample(b) Ten-second stirring s
40、hall be performed after the 5-minute and 30-minute samples. The final sample shall be taken immediately after stirring for 10 seconds.(c) Skim dross from aluminum surface, cool, weigh and record as in Section 6.2.4.6.8 For canned hardeners, stir for 60 seconds starting 30 seconds after addition.6.8.
41、1 Samples (Section 6.2.5) shall be taken as follows:(a) Every 5 minutes for 30 minutes.(b) After the 30-minute sample, stir for 10 seconds, then take final sample.(c) Skim dross from aluminum surface, cool, weigh and record as in Section 6.2.4.6.9 All samples shall be identified sequentially.6.10 Ob
42、servations for bubbles, fumes, flames or odors shall be made and recorded.6.11 Record, in notebook, sample number, sampling time and temperature.6.12 Analysis - Prepare the disk samples for spectrochemical analyses by removing the sprue and scalping 14-22% of the disk thickness off the as-cast disk
43、face. Typical removal is 0.100 inch from the half-inch thick disk. Analyze (burn) the disk in at least two (2) locations (Figure 2). The spectrochemical analyses should be made within a 1/2-inch (12.7 mm) wide annular ring. The rings outer edge is 1/4 inch (6.33 mm) away from the outer edge of the d
44、isk (see Figure 3 in E716). The analyses is to be obtained using suitable reference materials (standards). Average the result of the two (2) burns and record the results.6.13 Calculation of Element Recovery6.13.1 Recovery is expressed as follows:RW W W E W EW EA H sn xns A sH Hn n x n=+ ( )= = =1110
45、0 ( )( )=W E Es s sn xnn n n 12Where:R = Recovery (%)Esn= Sample analysis, %, for hardener element in each respective sample taken:Esn=1= Starting molten base metal analysis, %, for hardener element (formerly E2)Esn=x= Final samples analysisEH= Element content, %, of hardener charged - actual conten
46、t reported by supplier, or as determined by purchaser.WA = Weight of starting aluminum melt, lbs. (g).WH= Weight of hardener added to melt, lbs. (g).Wsn= Weight of each respective sample taken, lbs. (g)n xn=1= Sum of series of samples, first to lastExample:WA= 9922g. WH= 147g. EH= 10.2% Ti (Supplier
47、)Time (min) Wsn(g) Esn (%)Wsn (Esn Esn=1)_ _ _ _0 (n=1)1 (n=2)2351015 (n=x)1191311451291271011420.0050.1280.1420.1450.1520.1530.15316.11319.86518.06018.66914.94821.016Wsn xnn=1= 894W E Es s sn xnn n n ( )= 12= 108.671Esn=1= 0.005% Esn=x= 0.153%R =+ ( ) ( )9922 147 894 0 153 9922 0 005 100147 10 2 10
48、8 67. . . 11403 775 49 61 1001499 4 108 67197 37= =. . . %6.14 Dross Formation Measurement6.14.1 Dross formation may be determined using the dross weight recorded from Sections 6.6.1 (c), 6.7.1 (c) or 6.8.1 (c). The percent of dross formed may be expressed as:DWW WDA H=+100where: D = Dross formed, p
49、ercentWD= Weight of drossWA= Net weight of aluminum meltWH= Weight of hardener added to melt 6.15 Metallographic Examination6.15.1 When metallographic examination is required, the analytical samples shall be cut to obtain a section from the mid-radius (approximately the same distance from the center as the analytical “burn” locations) of the piece (Fig
