Research And Development On ADI Cam Of Weaving Machinery

The key wear part of weaving machinery is the cams—directly affects the service life ofequipment, productive efficiency and the quality of the textiles and cost. Currently thematerial of cams used textile machinery is main medium-carbon that is made through variousprocesses such as forging, rough machining, quenching and tempering, surface quenching,tempering and fine grinding. But the material is low of material utilization ratio, high energyconsumption, high cost, and the hardening layer is thin, unstable quality, and the material isoften lead to fault because wear resistance is not enough or cracking.The Austempered Ductile Iron (ADI) was a kind of new high-tech engineering materialsdeveloped in recent 30 years. Its matrix organization is not only contain the acicular ferrite ofhigh strength and high wear resistance but also high toughness austenite. Spherical graphite inthe matrix organization are many functions such as lubrication, reducing wear, saving energy,reducing noise, improving material utilization rate and reducing cost. So ADI is the idealmaterial which manufactured cams of looms.This paper first analyzed friction and wear characteristics of metal materials, and thennot only researches on the experiment of ADI friction and wear, but also discussed frictionand wear characteristics of ADI of the different hardness under the condition of slidingfriction of no lubrication, and then analyses the wear mechanism. The results show that, in thesame temperature (910℃) of austenitic transition, when the isothermal quenching temperatureis range from 280℃to 380℃,acicular ferrite in the matrix is thick, so the ADI of highisothermal temperature not only has low initial hardness and intensity, but also a large amountof abrasion, but in the process of friction the more austenite of the matrix become moreapparent of the work-harden, faster fallen wear volumes, the harder grinding.The paper analysis the important role and the failure reasons of the cams in weavingmachinery. According to the characteristics of weaving machinery of special request,combined with the study results of the ADI friction and wear experiment, the paper not justdesign the chemical composition the cams of ADI looms, smelting, casting and the process ofheat treatment, but also determine the austenitic transition temperature of ADI cams from 860to 950℃, holding time from 2 to 2.5h; and then determine the isothermal quenchingtemperature from 300 to 350℃, holding time from 1.5 to 2.5 h.In this paper, under the conditions of no lubrication sliding friction, the ADI cams and 45steel cams are examined comparative experiments. The results show that: the ADI camssurface compressive stresses effect, the matrix high carbon austenitic part into firm crystal ormicrocrystalline marten site, improve surface hardness, improve the abrasion resistance; Andthe new times surface and ongoing process above, the grinding the more hard, wear volumesare smaller. Although 45 steel cams for hardening initial larger hardness, wear volumessmaller, but with the surface layer of the ground to quenching, hardness drop, wear volumes ismore and more big. With the friction time become more, the advantage of ADI cams that isthe ideal materials in place of cams 45 steel become obvious.