Tensile strength of Resin-coated Ceramic Sand at room temperature
(1) Device
Swy hydraulic strength testing machine; ZS-6 sample preparation device.
(2) Sample preparation
The "8" shaped standard sample is used for the tensile strength of coated sand at room temperature for casting.
(3) Test method
The tensile strength value of the sample at room temperature shall be determined according to the provisions of GB/T 2684-2009, and its bending strength value is twice the tensile strength value in the pressure gauge.
Hot bending strength of Resin-coated Ceramic Sand
The preparation and determination method of hot bending strength samples refer to the bending strength at room temperature. Hot bending strength after taking out the sample, put it on the testing machine immediately and gradually load it until the sample is broken. It is required to measure within 10s after taking out the sample.
Hot tensile strength of Resin-coated Ceramic Sand
The preparation and determination methods of hot tensile strength samples refer to the tensile strength at room temperature. Hot bending strength after taking out the sample, load it gradually on the testing machine immediately until the sample is broken. It is required to measure within 10s after taking out the sample.
Loss on ignition of Resin-coated Ceramic Sand
(1) Definition
The loss on ignition of coated sand represents the percentage of total combustible and volatile substances in coated sand.
(2) Detection device
High temperature box type resistance furnace; A balance with an accuracy of 0.001 g; Magnetic boat.
(3) Test method
Firstly, the porcelain boat which has been calcined at 1 000 ± 5 ℃ for 30min to constant weight is placed in a dryer and cooled to room temperature for standby, and the mass of the porcelain boat is weighed at the same time. Weigh 2g (accurate to 0.001 g) of coated sand sample to be tested in the baked porcelain boat, and weigh the mass of the porcelain boat at this time (together with the coated sand put in). Then they are put into a high-temperature box type resistance furnace which has been heated to 1000 ± 5 ℃ and burned for 30 min. Take out the porcelain and put it into the dryer. After cooling to room temperature, weigh the mass of the porcelain boat again (together with the burned coated sand).
Fluidity of Resin-coated Ceramic Sand
(1) Definition
It refers to the relative movement ability of coated sand particles under the action of self weight.
(2) Device
The device is a 6 mm standard flow cup.
(3) Test method
Plug the bottom hole of the standard flow cup by hand, then fill up the coated sand, scrape it flat, remove your finger and start counting with a stopwatch until the sand is finished.
(4) Calculation
The time measured by the stopwatch is the measured value of the sand fluidity, with the unit of S.
Gas evolution of Resin-coated Ceramic Sand
(1) Device
Get-iii gas evolution tester; A balance with an accuracy of 0.001 g; Porcelain boat.
(2) Sample preparation
The sand ground from the fracture of the coated sand tensile strength sample at room temperature is used as the sample for measuring the gas evolution and stored in the dryer.
(3) Test method
Raise the temperature of the gas evolution tester to 1000 ± 5 ℃, weigh 1 ± 0.01 g sample, and evenly place it in a porcelain boat (the porcelain boat is burned at 1000 main 5℃ for 30 min in advance and then placed in a dryer to cool to room temperature for use), then quickly send the porcelain boat to the red hot part of the quartz tube and close the nozzle, the recorder starts to record the gas evolution of the sample, and read the maximum data recorded by the tester as the gas evolution value of the sample within 3 min.