摘要
磨盘是高浓磨机中易损件,其使用寿命直接影响着纸浆质量和生产效率。本文研究开发一套长寿纸浆磨盘的精密成形新技术。获得的主要成果如下:
系统研究了磨盘的失效模式和失效机理,发现纸浆磨盘的失效是由摩擦磨损、齿纹断裂、汽蚀、腐蚀及边缘磨损等几种失效模式复合作用引起的。摩擦磨损作为软磨料,主要由塑变疲劳引起,其过程首先是在基体与碳化物周围形成空洞,随着空洞的不断扩展,形成裂纹,裂纹不断扩展,相互连接,最终导致基体的剥落和碳化物的脱落。腐蚀不仅仅是齿与齿槽之间的电位差造成,还与材料基体与碳化物之间的电位差有关。
对汽蚀失效进行了系统的理论分析,建立了形成汽蚀必要条件的判据。认为磨区的压力降造成汽泡的产生,是产生汽蚀的必要条件,而且建立了判据:≤0,当该公式成立时,容易产生汽泡。汽泡爆破冲击齿区。在汽泡爆破冲击力及射流的复合作用下,导致材料受损。
研究了C、Cr、Mo以及Ni等元素对高铬合金材料性能的影响,随碳含量的增加,高铬合金材料硬度提高,冲击韧性降低。Cr含量的增加,硬度与冲击韧性都有所增加。随着Mo含量的增加,硬度跟冲击韧性都有所增加。随着Ni含量的增加,硬度递减,冲击韧性先增后减。筛选出一种优质的新型磨盘材料Cr27Mo2Ni-GT作为磨盘使用材料用于生产。
采用电磁振荡法、旋转法、极化曲线法以及滑动摩擦法,研究了不同材料耐汽蚀、抗冲刷、耐腐蚀和抗磨等性能。发现片状碳化物在中性和碱性条件下,具有良好的抗汽蚀、耐腐蚀、抗冲刷以及耐摩擦磨损;网状的碳化物严重影响材料的性能,各项指标都处于最低状态。岛状碳化物比片状碳化物更耐腐蚀、耐汽蚀,但在耐摩擦和冲刷方面不如后者。同时探明马氏体组织具有比奥氏体好的耐腐、抗汽蚀以及抗冲刷的能力。
提出由具有激冷功能、强度高、发气性低的面砂和背砂组合的壳型精密铸造工艺,设计出成套的造型工艺装备,对浇注工艺参数进行了优化。确定小磨盘浇注温度为1520℃,浇注时间2-3s,浇道为半闭半式,F直:F横:F内为1.25:1:1.72。大磨盘浇注温度为1610℃,其F直:F横:F内为1:1.42:3.28。有效地防止气孔、缩孔、缩松以及冷隔的发生,稳定生产出尺寸精度CT8级,齿纹区表面粗糙度Ra3.2um的磨盘铸件,其使用寿命达到设计要求。采用本研究成果的精密成形技术生产的磨盘产品,已在国内广泛使用。
Refiner plate is an easily broken part of high consistency disc refiner. Its service life span directly affects pulp quality and production efficiency. This paper studied the new precision form technology of long life pulp refiner plate. The main results followed as:
Failure modes and theories of refiner plate were studied systematically. It was found that failure of refiner plate is caused by the compound action of wear abrasion, tooth breakage, erosion, corrosion and bar rounding etc. Wear abrasion is caused by galling fatigue. The procedure is that pore occurred at the side of matrix and carbide firstly. Then cracks begin to generate with pore extending. At last matrix and carbide fall off, because of crack extending and connecting. Corrosion is not only affected by potential difference between tooth and groove but also by between matrix and carbide.
Erosion failure was systematically analyzed and the necessary condition criterion of erosion formation was deduced. It was considered that bubble generation is caused by pressure loss of refiner area, which is the necessary condition of erosion generation. The criterion is ≤0. When this formula value is less than or equal to zero, the bubble easily generates. Bubble blast attacks tooth area. The compound action of bubble blast and jet fluid results in material damage.
The effects of element C, Cr, Mo and Ni on the properties of high chromium alloy material have been investigated. The more increases C content, the more improves hardness of high chromium alloy material and the less impact toughness. Hardness and impact toughness rise with increasing Cr and Mo. Hardness decreases with increasing Ni, but impact toughness firstly increases, then decreases. The new refiner plate material-Cr27Mo2Ni-GT is optimized and developed.
By using ultrasonic vibratory method, rotating method, polarization curve method
and sliding friction method, the different material properties of erosion resistance, corrosion resistance, scour resistance and frictional wear resistance were investigated. It was demonstrated the material with flaky carbide have good properties of erosion resistance, corrosion resistance, scour resistance and frictional wear resistance. Net carbide badly affects the material properties and results in every index being the lowest. Island carbide has better properties than flake carbide on corrosion consistence and erosion consistence. But its properties are not as good as material with flake carbide on scour resistance and frictional wear resistance. At the same time it was proved martensite structure has better properties than austenite on corrosion resistance, erosion resistance and scour resistance.
It was presented that the shell precision casting process composed of back sand and facing sand with chilling, high strength and low gas-forming properties. A set of molding process and equipment was designed. Pouring parameters were optimized. Pouring temperature of small refiner plate was 1520℃. Pouring time was 2-3s. F直:F横:F内 was 1.25:1:1.72. Pouring temperature of large refiner plate was 1610℃. F直:F横:F内 was 1:1.42:3.28. Generation of pore by gas, shrinkage, dispersed shrinkage and cold shut was prevented by presents ways. Dimensional accuracy of stably produced casting was CT8. Tooth face roughness was Ra3.2um. Its life span met design requirement. Produced casting by using this precision process was extensively used in many plants.
引文
汤邦权. 现代制浆设备,轻工业出版社,1983
James P. Casey. Pulp and Paper. Chemistry and Chemical Technology. Third Edition, Volume 1,1979
制浆造纸工艺.华南工学院合编,轻工出版社,1982
D.Ouellet, C.P.J.Bennington, D.Potkins. Wood comminution and material flow in a laboratory chip refiner. Journal of Pulp and Paper Science, 1995,vol.21 No.12, (11):415-420
D.Atack, M.I.Stationwala, A.Karnis. What happens in refining. Pulp & Paper Canada 85,12 (1984):119-124
制浆造纸机械与设备. 华南工学院合编,轻工出版社,1981
黄方,杨春晖.盘磨机新型磨片.纸和造纸,1999(2):31
张进先.砂轮磨盘磨草浆的效果好.纸和造纸,2003(1):29
C.B.Thompson, A.Garner. The resistance of refiner plate alloys to bar rounding. Tappi Journal, 1988,82(6):95-100.
W.C.Frazier,W.H.Arnold,T.C.Williams,R.S.Charlton. Performance, design and metallurgy of refiner plates for TMP. Pulp & Paper Canada, 1981(3):80-85
汤晓华,朱庆文,孙美玉等. 纤维板热磨机磨片材料的研究. 东北林业大学学报. 1996 ,(2):48-52
周维平,李志章,凌国平等. 磨浆机磨盘失效分析及新磨盘钢的研制. 浙江大学学报, 1994,(1):18-25
Le Gall, R. Dazelle,G, Danylova. Witzke. S. Effect of sulfur and phosphorus on ductility of as cast iron-nickel-chromium alloys, direct observations on in-situ fractured surface by AES and TEM. Materials Science Forum, v 426-432, n 2, 2003, p 1041-1046
G.A Isaev, O.O.Suetov, G.Rudo. CO2 - process using a resin. Liteinoe Proizvodstvo, n 4, Apr, 1997, p 15
B.Andrew. Assessment of the control of finning (veining) defects in iron castings produced with phenolic-urethane cold-box bonded cores. Foundryman, v 94, n 1, Jan, 2001, p 13-21
Adler, A.Thomas, Dogan, N.Omer. Damage by indentation and single impact of hard particles on a high chromium white cast iron Wear, v 203-204, Mar, 1997, p 257-266
H.Oh, S.Lee, J.-Y.Jung, S.Ahn. Correlation of microstructure with the wear resistance and fracture toughness of duocast materials composed of high-chromium white cast iron and low-chromium steel. Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science, v 32, n 3, March, 2001, p 515-524
G.Yingfeng, J.Zhanpeng. Study on the structure and properties of high chromium white cast iron and its tempering standard Journal of Central South University of Technology v 6, n 1, May, 1999, p 8-12
L.Jinhai. L.Gensheng. L.Guolu. W.Kunjun. Z.Daben. Research and application of as-cast wear resistance high chromium cast iron. Chinese Journal of Mechanical Engineering v 11, n 2, Jun, 1998, p 130-135
G.Pintaude. A.P.Tschiptschin. D.K.Tanaka. A.Sinatora. The particle size effect on abrasive wear of high-chromium white cast iron mill balls. Wear v 250-251, n PART 1, October, 2001, p 66-70
J.T.H.Pearce. High chromium cast irons to resist abrasive wear. Foundryman v 95, n 4, April, 2002, p 156-166
C.P.Tabrett. I.R.Sare. Fracture toughness of high-chromium white irons: Influence of cast structure. Journal of Materials Science v 35, n 8, Apr, 2000, p 2069-2077
O.N.Dogan. J.A.Hawk. G.II.Laird. Solidification structure and abrasion resistance of high chromium white irons. Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science v 28A, n 6, Jun, 1997, p 1315-1328
G.Yingfeng. J.Zhanpeng. Study on the structure and properties of high chromium white cast iron and its tempering standard. Journal of Central South University of Technology v 6, n 1, May, 1999, p 8-12
C.P.Tabrett. I.R.Sare. Fracture toughness of high-chromium white irons: Influence of cast structure. Journal of Materials Science v 35, n 8, Apr, 2000, p 2069-2077
J.A.Pero-Sanz. D.Plaza. J.I.Verdeja. J.Asensio. Metallographic characterization of hypoeutectic martensitic white cast irons: Fe-C-Cr system. Materials Characterization v 43, n 1, Jul, 1999, p 33-39
JacksonR.S. Journal of the Iron and Steel Institute, 1970,(3):163-167
Гapбep M.E. Отливки из Белых Износостойких Чугунов Maщиностроение.1972,6-7
F.Maratray etal. Factors Affacting the Structure of Chromium and Chromium-Molybdenum White Irons, Climax Molybdenum Co.,1970
A.Kootsookos. J.D.Gates. The effect of the reduction of carbon content on the toughness of high chromium white irons in the as-cast state. Journal of Materials Science v 39, n 1, Jan 1, 2004, p 73-84
A.Drotlew. M.Garbiak. Relationship between moulding sand composition and size of carbide particles in white cast iron. Metalurgija/Metallurgy v 40, n 1, Jan, 2001, p 41-45
E.Albertin. A.Sinatora. Effect of carbide fraction and matrix microstructure on the wear of cast iron balls tested in a laboratory ball mill. Wear v 250-251, n PART 1, October, 2001, p 492-501
V.M.Sadovsky. Effect of carbon and chromium contents on the properties of high-chromium iron. Liteinoe Proizvodstvo n 5, May 1, 1998, p 12-13
饶启昌,高义民,刘福玲. 高铬铸铁三体腐蚀磨损机理及影响因素的研究.西安交通大学学报,1992,26(1):53-61
饶启昌,张金柱,高义民,刘福玲. 介质酸根对高铬铸铁腐蚀磨损特性的影响.西安
交通大学学报,1993,27(3):6
E.Zumelzu. I.Goyos. C.Cabezas. O.Opitz. A.Parada. Wear and corrosion behaviour of high-chromium (14-30% Cr) cast iron alloys. Journal of Materials Processing Technology v 128, n 1-3, Oct 6, 2002, p 250-255
Adler. A.Thomas. Dogan. N.Omer. Erosive wear and impact damage of high-chromium white cast irons. Wear v 225-229, n I, Apr, 1999, p 174-180
饶启昌,高义民,刘福玲等. 稀土对高铬铸铁三体腐蚀磨损特性的影响.摩擦磨损,1989,(4):32-36
Y.Matsuban. Eutectic solidification of high chromium cast iron-eutectic structure and their quantitation, AFS Transactions,1981:245-251
A.B.Jacuinde. W.M.Rainforth. The wear behaviour of high-chromium white cast irons as a function of silicon and Mischmetal content. Wear v 250-251, n PART 1, October, 2001, p 449-461
G.Powell. V.Randle. Effect of Si on the relationship between orientation and carbide morphology in high chromium white irons. Journal of Materials Science v 32, n 3, Feb 1, 1997, p 561-565
L.Jinhai. L.Gensheng. L.Guolu. W.Kunjun Z.Daben. Research and application of as-cast wear resistance high chromium cast iron. Chinese Journal of Mechanical Engineering v 11, n 2, Jun, 1998, p 130-135
P.Dupin, J.Saverna, J.M.Schissler. A structure study of chromium white cast irons. AFS Transaction, 1982,(90)711-718
Liu Fu-ling, Rao Qi-chang, Jin Zhi-hao. An investigation of corrosion-abrasion wear behavior of 6% Cr Martensitic cast steel. Journal of Materials Processing Technology, 1999,(95):180-184
饶启昌,高义民,张金柱等. 介质酸根与浆料条件对高铬铸铁腐蚀磨损特性的影响. 第六届全国金属耐磨材料学术会议论文集,1992,70-73
Ma Nai-heng, Rao Qi-chang, Zhou Qing-de. Corrosion-abrasion wear resistance of
28% Cr white cast iron containing boron. Wear,1989,(132):347-359
F.Maratray etal. Factors Affacting the Structure of Chromium and Chromium-Molybdenum White Irons, Climax Molybdenum Co.,1970
黄新民,张国荣. Mo对高铬铸铁组织结构的影响.机械工程学报,1994,30(3):19-23
M.M.Arikan, H.Cimenoglu, E.S.Kayali. Effect of titanium on the abrasion resistance of 15Cr-3Mo white cast iron. Wear v 247, n 2, Feb, 2001, p 231-235
姜镇崧. 稀土硅铁孕育对高铬合金白口铸铁性能的影响. 稀土,1997,(1):33-40
杨文涛. 稀土对高铬铸铁抗磨损及抗冲击剥落性能的影响. 湖南冶金,1999,(5):34-37
吴世常. 高铬铸铁复合变质剂的研究. 沈阳工业大学学报,1998,(1):85-90
Y.Qingxiang. L.Bo. L.Jianhua. Y.Mei. Effect of rare earth elements on carbide morphology and phase transformation dynamics of high Ni-Cr alloy cast iron. Journal of Rare Earths v 16, n 1, 1998, p 36-40
G.Chen. C.Wang. Inoculation mechanism of rare earth-Mg alloy in molten cast iron. Journal of Materials Science v 33, n 4, Feb 15, 1998, p 985-988
S.V.Kartoshkin, Kremnev, P.Yu. L.Ya.Kozlov. On joint influence of antimony and rare-earth metals on microstructure and properties of industrial cast iron. Izvestiya Vysshikh Uchebnykh Zavedenij. Chernaya Metallurgiya n 1, 2002, p 49-52
杨庆祥,赵亚坤等. 稀土对高铬铸铁碳化物形态及相变动力学的影响.中国稀土学报,1998,16(2):166-169
张洪波,吴德海. 稀土变质处理对高铬铸铁组织和性能的影响. 机械工艺师,1990,(8):14-15
邓海金. 湿磨条件下磨球的磨损及选材. 矿山机械,1988,(8):19-26
张清. 金属磨损和金属耐磨材料手册. 冶金工业,1991.1
K.Alexander. H.Cava, R.D.Mourisco, A.Kiminami, C.S.B.Claudemiro. Microstructure of spray formed 2.9%C-22%Cr high chromium white cast iron. Materials Science Forum v 416-418, n 1, 2003, p 419-424
D.N.Hanlon. Y.H.Li. W.M.Rainforth. C.M.Sellars. Formability of spray-formed, high-chromium content, white cast iron. Journal of Materials Science Letters v 17, n 19, Oct 1, 1998, p 1637-1640
Y.Matsubara. N.Sasaguri. K.Shimizu. S.Yu. K.Yu. Solidification and abrasion wear of white cast irons alloyed with 20% carbide forming elements. Wear v 250-251, n PART 1, October, 2001, p 502-510
Guo,M.L.Ted. C.Chun-Hsien Tsao, Y.A.Chi. Microstructure and wear behavior of spray-formed and conventionally cast rolls of 18Cr-2.5Mo-Fe alloy. Materials Science and Engineering A v 326, n 1, Mar 15, 2002, p 1-10
W.C.Frazier,W.H.Arnold,T.C.Williams,R.S.Charlton. Performance, design and metallurgy of refiner plates for TMP. Pulp & Paper Canada, 1981(3):80-85
李子全,朱平顺,郝远. 铸铁汽蚀破坏机制研讨. 甘肃工业大学学报,1991,(6):50-55
王久彬,李庆春. 高铬铸铁轧辊的力学性能. 国防工业出版社,1995
B.L. Browning. The chemistry of wood. R.E. Kreiger. Huntington. NY.1975
张剑锋,周志芳. 摩擦磨损与抗磨技术,天津科技翻译,1993
李华飞. 钢材热浸涂55%Al-Zn合金工艺及其性能的研究.博士学位论文. 武汉,华中科技大学,2001
C.B.Thompson. The Cavitation erosion resistance of refiner plate alloys. Journal of Pulp and Paper Science, 1990,(1):20-28
Hirth.J.P, Lothe J. Thoery of Dislocation,1982
邹鸿承,娄彦良,戴蜀娟等. 第二相粒子对材料延展性断裂过程的影响, 华中理工大学学报,1989,(2):57-62
范新会,贺林. 马氏体高铬铸铁抗磨料磨损与抗冲击疲劳性能的研究, 摩擦磨损,1989,(3):36-41
何奖爱,王玉玮. 材料磨损与耐磨材料. 东北大学出版社,2001
苏俊义.铬系耐磨白口铸铁. 国防工业出版社.1990
贺林,张长军. 高铬铸铁中碳化物相抗磨作用的“尺寸效应”. 热加工工
艺,1998,(4):15-18
C.B.Thompson. The Cavitation erosion resistance of refiner plate alloys. Journal of Pulp and Paper Science, 1990,(1):20-28
X.Jun. L.Wukui. W.Shuangjin. L.Hongping. W.Yonglin. X.Hongyuan. L.Xianwu L.Hanwei. High chromium cast iron Cr15Mo3 and its application in slurry pumps. Proceedings of the International Conference on Pumps and Fans, ICPF, 1998, p 723-728
M.Izciler. H.Celik. Two- and three-body abrasive wear behaviour of different heat-treated boron alloyed high chromium cast iron grinding balls. Journal of Materials Processing Technology v 105, n 3, Sep, 2000, p 237-245
K.Osara. T.Tiainen. Three-body impact wear study on conventional and new PM/ + HIPed wear resistant materials. Wear v 250-251, n PART 1, October, 2001, p 785-794
I.R.Sare. J.I.Mardel. A.J.Hill. Wear-resistant metallic and elastomeric materials in the mining and mineral processing industries - An overview. Wear v 250-251, n PART 1, October, 2001, p 1-10
S.Parent, J.C.Margerie. Mechanical properties and wear resistance of white cast iron. AFS Trans,1972,(80):393-400
R.B.Gundlach. Microstructure,hardness and abrasion resistance of as-cast 17.5% chromium white irons. AFS Trans, 1974(82):309-316
P.Dupin, J.Saverna, J.M.Schissler. A structure study of chromium white cast irons. AFS Transaction, 1982,(90)711-718
Xing J.D, Zhou Q.D. Influence of carbon content on oxidation and wear resistance of Fe-20%Cr alloy at elevated temperatures. AFS Trans, 1992,(100):17
Wu, Wen-Zhong, Xing, Jian-Dong, Su, Jun-Yi. Investigation on three-body abrasive wear test at elevated temperature. Wear, 1997,(210):299-303
C.H.Pitt, Y.M.Chang. Jet slurry corrosive wear of high-chromium cast iron and high-carbon steel grinding ball alloys. Corrosion, 1986,(42):312-317
A.Bronson, C.Kang, J.Nelson. Analysis of the scribing technique for determining the corrosive wear of an Fe-21wt.%Cr-19wt.%Ni alloy. Wear, 1992,(154):387-401
张安峰,邢建东,高义民等. Cr系白口铸铁的相间腐蚀机理及其电化学行为. 金属学报,2000,(7):765-769
J.T.H.Pearce. High chromium cast irons to resist abrasive wear. Foundryman, 2002(4):156-166
于福洲. 金属材料的耐腐蚀性.科学出版社,1982.3
腐蚀与防护手册, 耐蚀金属材料及防蚀技术化学工业部化工机械研究院, 化学工业出版社.1990
Y.Yoshinori. M.Michio. S.Keiichi. H.Shuji. Mechanism of cavitation erosion at the exit of a long orifice. Proceedings of the ASME/JSME Joint Fluids Engineering Conference v 1 B, 2003, p 1359-1364
I.Hiromu. T.Masatsugu. K.Hiroyuki. S.Tadashi. A study of cavitation erosion. 10th International Conference on Nuclear Engineering (ICONE 10), Apr 14-18 2002, Arlington, VA, United States
Y.Atsushi. T.Ichiro. T.Tatsuo. M.Yoichiro Prediction calculation of the cavitation erosion generated in connection with a high-pressure jet. Proceedings of the ASME/JSME Joint Fluids Engineering Conference v 1 B, 2003, p 1067-1071
M.Cudina. Detection of cavitation phenomenon in a centrifugal pump using audible sound. Mechanical Systems and Signal Processing v 17, n 6, November, 2003, p 1335-1347
S.Johannes. Method for the study of unsteady cavitation observations on collapsing sheet cavities. Doktorsavhandlingar vid Chalmers Tekniska Hogskola n 1587, 2000, p 1-126
D.Wang. Z.Li. Y.Zhu. Study of the key problems in a water hydraulic piston pump and its applications. Industrial Lubrication and Tribology v 53, n 5, September/October, 2001, p 211-216
H.W.Wang, M.M.Stack. Corrsion of PVD TiN coating under simultaneous erosion in sodium carbonate/bicarbonate buffered slurries. Surface & Coatings Technology, 1998, 105(1-2):141-146.
M.Elarabi, A.Mazur. Flow-line failure resulting from erosion-corrosion in a high production oil well. Materials Performance, 1985, (9):19-22
J.Postlethwaite. Control of erosion-corrosion in slurry pipelines. Materials Performance, 1987, 26(12):41-45
H.Nanjo,Y.Kurata,N.Sanada et al. Erosion corrosion damage of aluminum alloy in a High-speed, High-temperature, Two-phase slow. Wear, 1995,(2):573-578
A.Sakamoto,T.Yamasaki,M.Matsumura. Erosion-corrosion tests on copper-alloys for water tap use. Wear, 1995,186-187(2):548-554
B.Heeg,T.Moros,D.Klenerman. Persistency of corrosion inhibitor films on C-steel under multiphase flow conditions. Part1:The Jet-cylinder Arrangement. Corrosion Science, 1998,(8):1303-1311