Creepage stage determination systems and methods for aluminum-containing heat-resistant alloy furnace tubes
Creep stage determination system and method for aluminum-containing heat-resistant alloy furnace tube, the system includes: a micro-imaging unit, a display unit, a memory, and a processor, the micro-imaging unit configured to image specimen, the display unit configured to display a microstructure photograph of the specimen, the micro-imaging unit, the display unit, the memory and the processor are communicatively connected, and the processor is configured to: acquire at least one field-of-view image; for the field-of-view image, carry out image recognition on the field-of-view image to determine an eigenvalue of the field-of-view image; based on the eigenvalue of the at least one field-of-view image, determine a target creep value by a generative model; determine, based on the target creep value, the creep stage; and send the at least one field-of-view image and the creep stage to the display unit to display the at least one field-of-view image and the creep stage.
1. A creep stage determination method for an aluminum-containing heat-resistant alloy furnace tube at a temperature of 1100° C., comprising:
S 1 , performing microstructural observation and analysis at a 1/4-3/4 wall thickness part of a cross-section of the aluminum-containing heat-resistant alloy furnace tube, including:
measuring an area S1 of a peripheral lumpy precipitate M 23 C 6 -type carbide in an austenitic grain boundary precipitate of a furnace tube material within a field-of-view area S 0 , and determining an area fraction of the area S 1 of the peripheral lumpy precipitate M 23 C 6 -type carbide in the austenitic grain boundary precipitate to the field-of-view area S 0 as A=S 1 /S 0 ×100%, with a unit of 1;
measuring an area S 2 of an internal thin strip-like precipitate M 7 C 3 -type carbide in the austenitic grain boundary precipitate of the furnace tube material within the field-of-view area S 0 , and determining an area fraction of the area S 2 of the internal thin strip-like precipitate M 7 C 3 -type carbide in the austenitic grain boundary precipitate to the field-of-view area S 0 as B=S 2 /S 0 ×100%, with a unit of 1; and
measuring an aspect ratio C of the internal thin strip-like precipitate M 7 C 3 -type carbide in the austenitic grain boundary precipitate of the furnace tube material within the field-of-view area S 0 , with a unit of 1;
S 2 , determining an influence function of a creep stage of the aluminum-containing heat-resistant alloy furnace tube at 1100° C. based on the area fractions A and B and the aspect ratio C:
f ( A,B,C )=[( aA+bB+cC )/100]×100%
where a is 1200, b is −10, and c is −0.3;
S 3 , dividing the creep stage of the aluminum-containing heat-resistant alloy furnace tube at 1100° C., including:
if f(A,B,C)≤10%, determining a creep state of a 27Cr44Ni5W3Al+microalloyed furnace tube as a creep first stage;
if 10%<f(A,B,C)≤30%, determining the creep state of the 27Cr44Ni5W3Al+microalloyed furnace tube as an early phase of the creep second stage;
if 30%<f(A,B,C)≤70%, determining the creep state of the 27Cr44Ni5W3Al+microalloyed furnace tube as a mid-phase of the creep second stage; and
if 70%<f(A,B,C)≤90%, determining the creep state of the 27Cr44Ni5W3Al+microalloyed furnace tube as an end phase of the creep second stage.
2. The creep stage determination method of claim 1 , wherein the microstructural observation is performed using an Olympus® GX53 metallurgical microscope with a magnification of 1,000 times; and
no fewer than 20 fields of view are randomly selected fro each specimen for the microstructure observation.
3. The creep stage determination method of claim 1 , wherein microstructure analysis of microstructure photographs is performed using an Image Pro® Plus 6.0 image analysis software, and measurement data is an arithmetic mean of all fields of view measurements.
4. The creep stage determination method of claim 3 , wherein when using the Image Pro® Plus 6.0 image analysis software to perform the microstructure analysis of the microstructure photographs, regions are selected with a range of 10, a thresh of 3, a smooth of 1, and a speed of 2.
5. The creep stage determination method of claim 1 , wherein an austenite grain boundary and intragranular total precipitate of the furnace tube material comprises the M 23 C 6 -type carbide, the M 7 C 3 -type carbide, and a Ni 3 Al phase.
6. The creep stage determination method of claim 1 , wherein the aluminum-containing heat-resistant alloy furnace tube is the 27Cr44Ni5W3Al+microalloyed furnace tube.