1、FORD LABORATORY TEST METHOD BL 104-01 2001 0822 ALUMINUM CYLINDER HEAD HEAT-TRANSFER CORROSION TEST Revised Editorial - no technical change A. Cockman Application It is essential that engine coolants prevent internal heat-transfer corrosion of aluminum cylinder heads during engine operation. Any cor
2、rosion products formed will likely deposit on the nterior radiator surfaces, reducing the heat transfer efficiency of the radiator, or actually cause tube blockage. Over-heating and boil- over of the cooling system may then occur. This short-term screening test is used to evaluate the effectiveness
3、of inhibited engine coolants in preventing high temperature heat-transfer corrosion of aluminum cylinder heads. Apparatus Required Temperatu re Controller Athena, Model 2000B-16 F/C or equivalent, with temperature control range up to 150 OC. Use type ” J ” thermocouple . Band Heaters Hotwatt, 950 wa
4、tt standard construction band heaters or equivalent, 50 mm ID, 125 mm length, 120 volts AC, standard tightening clamp, type ”L” terminal. Ultrasonic Cleaner Bransonic Model 12, 1 quart, 50 watts, or equivalent. Vacuum Oven Thelco Model IO, to 150 OC, or equivalent. Vacuum Pump Ace-Nelson Model 91 1,
5、 or equivalent. Heat-Transfer Corrosion Cell 1. Glass -ring cell, pyrex, 53 cm long (see Figure 1). 2. O-rings, Viton. (Teflon is not suitable due to high creep rate at test temperature.) I Date I Action I Revisions I CopyrightO2001, Ford Global Technologies, Inc FORD LABORATORY TEST METHOD BL 104-0
6、1 3. Heat-transfer bar, steel (see Figure 2). 4. Top and bottom assembly plates, 316 stainless steel (see Figure 3). 5. Pressure gauge, O - 150 kPa 6. Threaded rods, 72 cm length, typically 114 - 20 UNC. 7. Heat-transfer test sample, casting alloy of interest (see Figure 2). Analyt ical Balan ce 160
7、 g minimum capacity with a precision of +/- 0.1 mg; Mettler Model No. H33AR. Curtis Matheson Catalog No. 368-522 or equivalent. Glass Capillary Pipet 150 mL Curtis Matheson Catalog No. 081 -91 9 or equivalent. Low Power Microscope Bausch and Lomb Model Z-3OLZ; Curtis Matheson Catalog No. 369-959 or
8、equivalent. Apparatus Required Soft Bristle Brush Thin Cotton Gloves Carborundum Paper Various grits (60-600). Distilled or Deionized Water 1 O ppm maximum dissolved solids per ASTM DI 888. Sodium Chloride (NaC1) Reagent Grade. Acetone Reagent Grade. Caution: Low flash point. Chromium Trioxide (Cr03
9、) Reagent Grade. Caution: Corrosive. Refer to Note (1) Chromic Acid Cleaning Solution Refer to Para 2 of this FLTM under cleaning of Aluminum Test Specimens. Caution: Corrosive. Refer to Note (1). Page 2 of 8 Copynght02001, Ford Global Technologies, Inc FORD LABORATORY TEST METHOD BL 104-01 Conditio
10、ning and Test Conditions All test values indicated herein are based on material conditioned in a controlled atmosphere of 23 +/- 2 OC and 50 +/- 5 % relative humidity for not less than 24 h prior to testing and tested under the same conditions unless otherwise specified. Procedure Preparation of Coo
11、lant Mixtures Prepare 1 liter of 25 % solution, sufficient for duplicate tests. Mix 250 mL of the coolant concentrate in 750 mL of distilled or deionized water. To this 1 liter mixture add 165 mg of sodium chloride (NaCI), either as the salt or as an aliquot from a previously prepared standard sodiu
12、m chloride solution. This will give 100 ppm of chloride ions in the final mixture. Analyze for inhibitor concentration and specific gravity. Preparation of Aluminum Test Specimen The following steps are necessary in the preparation of the aluminum test specimen for maximum accuracy and reproducibili
13、ty. The test samples may be reused. 1. Flat polish test samples with carborundum paper to remove any gross surface defects of previous corrosion damage. The final surface polish is with 600 grit paper. 2. Wash test sample with warm tap water, then rinse with distilled or deionized water, and finally
14、 with acetone. Make sure thermocouple holes are free of metal chips and polishing debris. Flush holes well with acetone, and remove excess liquid. A glass capillary pipet is suitable for this purpose. 3. Dry test specimen in a vacuum oven for several hours at 65 - 90 OC. Since most castings have som
15、e porosity this procedure is necessary to ensure removal of any residual liquid. From this point, test specimen should not be handled with bare hands in order to avoid weighing errors. Thin cotton gloves, Kodak or equivalent, are suitable for handling. 4. Cool specimen to 23 +/- 2 OC, weigh on an an
16、alytical balance to 0.1 mg. 5. Assemble test specimen into test cell, avoiding mechanical damage. Test Cell Operation 1. Assemble cell according to Figure 1. New Viton Orings should be used between the aluminum test specimen and glass cell for each test. During assembly make sure -rings are properly
17、 seated and avoid overtightening threaded rod nuts. Page 3 of 8 Copynght02001, Ford Global Technologies, Inc FORD LABORATORY TEST METHOD BL 104-01 2. Fill cell with 500 mL of test coolant, place plug in fill hole, pressurize to 150 kPa and turn on band heater. 3. Adjust temperature to 135 +/- 2 OC w
18、ith temperature controller. Temperature at auxiliary thermocouple hole should be monitored occasionally with a precision potentiometer. Cell is operated continuously at this temperature for 168 hours. 4. At end of test, turn off heater and allow test cell to cool to 23 +/-2 OC before disassembly. Re
19、tain coolant solution for analysis (inhibitor concentration and specific gravity). After disassembly, glass cell should be cleaned with a large bristle brush, detergent and water. If deposits are not removed with this procedure, glass cell should be immersed in chromic acid cleaning solution until c
20、lean. Cleaning of Aluminum Test Specimens 1. Wash specimen with a soft bristle brush using a mild detergent. 2. Immerse specimen in a small dish or beaker containing the following cleaning solution for 50 minutes at 80 OC: 475 mL distilled or deionized water 25 mL concentrated phosphoric acid 1 O g
21、Cr03 (chromium trioxide) Occasionally brush the surface with a soft bristle brush. At the end of 5 minutes, transfer the beaker containing the aluminum test specimen and cleaning solution to an ultrasonic cleaning unit, and apply power for 1 minute. 3. Remove test specimen from cleaning solution, fl
22、ush well with tap water, followed with distilled or deionized water, and finally acetone. Make sure thermocouple holes are flushed well and excess liquid is removed. Inspect surface using low power microscope. If any deposits remain, repeat steps 2 and 3. 4. Dry in vacuum oven using the same procedu
23、re and precautions as outlined in the Preparation of Aluminum Test Specimens, Step 3. 5. Cool to 23 +/- 2 OC and weigh. Calculation of Corrosion Rate 1. Before the corrosion rate can be calculated, it is necessary to include a “blank“ correction. The “blank“ is the weight loss due to the chromic aci
24、d and ultrasonic cleaning (Steps 1 - 5 of Cleaning of Aluminum Test Specimens), and should be added to the weight of the test specimen after the heat-flux test. Several specimens should be used to determine this “blank“ value, using the mean value. Page 4 of 8 Copynght02001, Ford Global Technologies
25、, Inc FORD LABORATORY TEST METHOD BL 104-01 2. Calculate the corrosion rate with the following formula: Corrosion Rate = Wh - (W, + BI A Wb = weight of test specimen before heat-flux test W, = weight of test specimen after heat-flux test B = weight loss of “blank“ A = heat-flux surface area (inside
26、O-ring) 3. A typical calculation is shown below: Wb = 105.1064 W, = 104.9196 B = 0.0013 A = 20.42 cm2 Corrosion Rate = 105.1 064 - (1 04.91 96 + 0.001 3) 20.42 = 0.0091 g/cm2 = 9.1 mg/cm2 Since the test was run for 1 week, the final corrosion rate is: 9.1 mg/cm2 /week Chemicals, materials, parts, an
27、d equipment referenced in this document must be used and handled properly. Each party is responsible for determining proper use and handling in its facilities. Page 5 of 8 Copynght02001, Ford Global Technologies, Inc FORD LABORATORY TEST METHOD BL 104-01 ALUMINUM CYLINDER HEAD HEAT-TRANSFER CORROSIO
28、N TEST ASSEMBLY 7 PRESSURE GAUGE TOP ASSEMBLY PLATE THREADED ROD, 114 x 20 TEST COOLANT LEVEL, 500 ML #40 PYREX O-RING CELL, 53 CM LENGTH THERMOCOUPLE HOLE VITON O-RING ALUMINUM TEST SPECIMEN /- STEEL HEAT TRANSFER BAR : BOTTOM ASSEMBLY PLATE /-950 WATT BAND HEATER fl II III Figure 1 Page 6 of 8 Cop
29、ynght02001, Ford Global Technologies, Inc FORD LABORATORY TEST METHOD BL 104-01 ALUMINUM CYLINDER HEAT-TRANSFER CORROSION TEST ASSEMBLY Thermocouple Hole Drill to Fit I _ .-o.-o- Auxilliary thermocouple Hole Aluminum Electrode 12 Heat Transfer Bar (steel) Figure 2 Page 7 of 8 Copynght02001, Ford Glo
30、bal Technologies, Inc FORD LABORATORY TEST METHOD BL 104-01 ALUMINUM CYLINDER HEAD-TRANSFER CORROSION TEST ASSEMBLY TOP ASY PLATE 1/8 PIPE - 2 HOLES - 1 6- f - - / 15.9 2 / / 7.9 DIA - 52.4 DIA - BOTTOM ASY PLATE ; 4 “-“-f 31.8 41.3 _.-._ i .- f 114.3 SQUARE Figure 3 Page 8 of 8 Copynght02001, Ford Global Technologies, Inc
