Research On Influence Of Composite Effect Of Plure Low Alloys On The Funcition Of Gray Iron Castings On The Motors

This thesis looks upon high strength gray iron castings flywheel on the motors as an object of study,it begins on the forming mechanism of the foundry organization of gray iron,and on the main factors influencing on the organization and properties of gray iron,and in view of theories of straight crossing tests,getting through systematic tests and studies,by analysing square disparity of the experimental data,gaining the influence law of composite effect of plure low alloying on the mechanical funcitions of gray iron castings on the motors,possessing better practical value.This thesis researchs the main factors influencing on the organization and properties of iron casting,such as furnace material characteristics,chemical composition,meting temperature,purity of liquid iron,inoculation and speed of cooling of high strength gray iron castings flywheel,it explories the forming mechanism of the foundry organization of gray iron,gaining the influence laws of the items listed above on the organization and properties of iron castings.It has a certion degree guiding action to the production of gray iron castings on the motors,and to improving the quality of the prouducts.Using the technology of plure low alloying and the theory of straight crossing tests,it decides on the entire plan of tests and studies systematicly,by combining production tests and examining quality of material of castings,analysing and researching the process of founding and crystallizing/solidifying of of high strength gray iron castings flywheel,explorying the effect of alloy elements(such as Cu,Mo and Cr)on the mechanical funcitions of gray iron castings flywheel,summarizing the influence law of composite effect of three sorts of alloy elements(such as Cu,Mo and Cr)on the mechanical funcitions of gray iron castings on the motors.It provides a set of efficacious technical methods for the production of high strength gray iron castings on the motors.In this thesis,tests and studies are in view of existing conditions of productoin and tests in our corporation,researching the influence of alloying the cast iron with Cu,Mo,Cr multiple elements on the metallography structure and mechanical capabilities of high strength gray iron flywheels.By tests and studies,it is confirmed what is the best matching dosage of alloy elements(such as Cu,Mo and Cr)in gray iron castings.Result of the experiments indicates that molybdenum is the best one to improve the metallography structure and raise the mechanical properties of gray iron,the effect of copper is less than molybdenum,the impact of chromium is not obvious,among the three sorts of alloy elements which is used in the gray iron castings.The production of this test and study has been put into use for manufacturing engine flywheel castings which belongs to high strength gray iron in our corporation.And the favorable actual effect can be gained in this application.Under reasonably adding alloy elements of Cu,Mo and Cr,we can manufacture flywheel castings with the material quality of HT350,filling the gap of productoin in our corporation,In addition,under the conditions of only adding alloy elements of Cu and Cr,the tensile intensity of gray iron castings can be increased upto 300 MPa,without addition of Mo which price is very expensive.At the same time,the quality and performance of flywheel castings can satisfy the design request.It can bring low cost and favorable economy benefit obviously.