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Graphite Morphology Transition in Ductile Iron during Liquid Isothermal11

Transition of Graphite Morphology

during Liquid Holding of Ductile Iron

School of Material Science and Engineering, Harbin Institute of Technology, Harbin

150001, P R China

Abstract:Transition process of graphite morphology of ductile iron during a long time liquid holding of iron melt was studied by quenching specimens using optical and scanning electron microscopy. Results show that spheroidal graphite is only observed at the early stage of the liquid holding. There are no evident changes in both morphology and size of spheroidal graphite, while the number decreases to some extent with increasing holding time up to 180min. Chunky graphite precipitates directly during liquid holding as spheroidizing ability is not sufficient after holding for 240min. The number and size of eutectic chunky graphite cells increase with prolonged time. Subsequently vermicular graphite forms around eutectic chunky graphite cells as the solidification progresses. When holding time reaches 420min, graphite in the microstructure is nearly flake. The graphite morphology of quenched specimen changes from spherical to chunky, then vermicular and finally to flake with an increase in liquid holding time.

Keywords: Ductile iron; liquid holding; graphite morphology transition; spheroidizing elements 1 Introduction

Graphite morphology in ductile iron can be changed from one form to another over a wide range of graphite formation by altering the solidification cooling rate, inoculation level, and/or the amount of spheroidizing elements present such as magnesium or rare earths. The microstructure and especially the morphology of the precipitated graphite determine the mechanical properties of ductile iron[1,2,3,4,5]. However, ductile irons suffer from non-spherical graphite formation during solidification in heavy-section castings, which is detrimental to the mechanical properties[6,7]and restricts its applications[8,9,10,11,12]. Among the various forms of non-spherical graphite, also called degenerate graphite, chunky graphite at the thermal center in heavy section is the most incomprehensible phenomenon on the production of ductile iron castings.

Controlling morphology of graphite in cast iron has been the subject of several research projects all around the world, but it is still not fully understood[13-19].In order to minimize non-spherical graphite formation, chills are normally used in the design, which reduces degenerate graphite level sometimes[13,14],but this becomes very limited to thickness up to a few centimeters.

G.F.Geier, et al[15]concluded that there is little difference between the morphologies displayed in the well-formed compacted graphite whether treated with Mg, Ce or La. However, the transition from compacted to lamellar shape is continuous for Mg treatment, whereas there is a sharp transition when treated with rare earth elements (Ce or La).

Fang Keming et al[16]suggested that excessive spheroidizing elements concentrations cause the formation of non-spheroidal graphite in heavy section ductile iron as a result of segregation of these elements in the last solidified area. Shoji

Kiguchi et al[12,17] also mentioned that chunky graphite was formed by the growth of graphite with sufficient spheroidizing ability. However, they advocate that basal plain of graphite expands predominantly causing chunky graphite formation, which is different from Fang’s conclusions.

Contrary to Fang Keming et al[16]and Shoji Kiguchi et al[12,17], R.K?llbom, et al[18,19] found that the growth pattern changed to a more spherical morphology because of Mg segregation at the outer regions of the eutectic chunky graphite cells, which is the last solidified area. They suggested that low local content of Mg would promote the chunky graphite formation and growth. However, the reason to form chunky graphite instead of vermicular graphite is still a problem to perplex the researchers.

As a matter of fact, while considerable literature exists concerning transition of graphite morphology in heavy section castings, much of the literature appears to be contradictory. In the present research, efforts have been focused on morphology of graphite during liquid holding to identify its transition process. In order to better understand solidification process of heavy section ductile iron, a series of quenched samples during the long time holding of ductile iron were analyzed.

2 Experimental procedures

The melting process was carried out in a medium frequency induction furnace of 20 kg capacity. Furnace charge for the selected composition consisted of steel srap, pig iron, and carbon additive. In each case, the initial charge was heated up to 1400℃, and then the melt was poured to the ladle, in which desulfurizer was placed to lower the base sulfur content. The melt was reheated to 1520℃～1550℃to destroy any possible pre-existing nuclei before being poured into a preheated ladle for nodularisation and inoculation treatment by sandwich method. After that inoculants were added to the melt in the ladle and fully stirred mechanically in order to ensure an even distribution. Then liquid iron of about 2 Kg was poured into graphite crucible preheated at 1320℃in MoSi2furnace and held at the temperatures as design. The experimental apparatus is shown in Fig. 1. The furnace temperature was accurately controlled by dipping Pt-Rh/Pt（S-type）thermocouple into the molten metal. Chemical composition of the nodularizer, inoculant and the resulting casting are shown in Table 1.

In the experimental furnace, liquid iron was cooled and solidified according to the schedule in Fig. 2 using furnace controller. Each liquid iron was quenched by a 5mm quartz tube at at regular intervals (0, 60, 120, 180, 240, 300, 360, 420min). Samples for microstructure analysis were cut from quenched sample close to the bottom of specimen. The cross section of the specimen were ground and polished according to standard metallographic procedures and examined by optical microscopy. For scanning electron microscope (SEM) observation, samples were treated by electrolytic etching or electrolytic extraction[20].

Table 1 Chemical compositions of nodularizer, inoculant and the resulting casting (wt ％) Element

C Si Mn S P Mg RE a Sb Ca Ba Fe Nodularizer

— 43.67 — — — 8.28 3.14 0.53 3.1 2.3 Bal. Inoculant

— 68.32 — — — — — — 0.86 2.07 Bal. Specimen

3.52 2.0 0.13 0.012 0.034 0.037 0.026 0.008 — — Bal. a RE is the misch metal, containing 50%Ce and 50%Y , respectively.

Fig. 1 Experimental apparatus for simulative solidification

1 Ceramic wool (Hi-Al 2O 3)

2 Firebrick

3 MoSi 2 heater

4 Graphite crucible

5 Liquid iron

6 Steel lid

7 Thermocouple (Pt-PtRh) recorder

8 Steel frame

9 Thermocouple (Pt-PtRh) controller

T e m p e r a t u r e ,℃Time,min

Fig. 2 Cooling curve of iron melt and quenched points during solidification

3 Results

3.1 Transition of graphite morphology

Graphite morphology transition process by quenched melt iron every 60min is presented in Fig. 3. It is clear that spheroidal graphite directly precipitates in liquid iron as primary graphite at the early stage of liquid holding. Holding time has little or

no evident effect on morphology and size of spheroidal graphite up to 180min, as shown in Fig. 3(a)-(d), which is the maximum time necessary for the maintaining of the formation of speroidal graphite, but the number of spheroidal graphite was decreased significantly as the holding going on. According to the results mentioned above, it can be deduced that there is no graphite existing in melt iron within 180min, while temperature is above 1200℃. All the graphite in the specimen is precipitated directly during quenching. From Fig. 3(e)-(h) one can see that the spheroidal graphite can hardly be found in the microstructure at holding time longer than 180min. (180-240) In other words, increasing of holding time from 240 to 420min, the graphite shape changes from speroidal to chunky, then vermicular and eventually to flake-like form, as demonstrated in Fig. 3(e)-(h).

Fig. 3(e) shows that the precipitation of chunky graphite begins to be observed in the specimen when holding time reaches 240min at 1200℃. Chunky graphite coexists with seldom spheroidal graphite at this quenching point. Fig. 3(f) shows a representative eutectic cell of chunky graphite, the size of which is about 100μm-200μm, much bigger than that of spheroidal graphite. The number of chunky graphite increases sharply when holding time reaches 360min as shown in Fig. 3(g). In the meanwhile, newly precipitated vermicular graphite can also be found around large chunky graphite eutectic cell. Nearly fully flake graphite is shown in Fig. 3(h), which is held for 420 min in the furnace before quenched.

Fig. 3 Microstructure of specimen quenched after holding for different times

(a)

0 min; (b) 60 min; (c) 120 min; (d) 180 min; (e) 240 min; (f) 300 min; (g) 360 min; (h) 420min

Fig. 4 shows the microstructure of ductile iron after 420 min holding and completely solidified in the furnace without any quenching, in which the flake graphite is full of the whole specimen and there is no spheroidal graphite found. Compared with Fig. 3(h), the size of flake graphite increased significantly.

Fig. 4 Graphite morphology in as-cast microstructure after liquid holding for 420 min and

solidified in the furnace

(a) 2-D; (b) 3-D

3.2 3-D morphology of spheroidal and chunky graphite

Fig. 5 shows the morphology of spheroidal graphite at the very beginning of liquid holding. All the graphite is nearly sheroidal, and size distribution is rather

uniform. Non-spherical graphite hardly can be seen. Fig.6 presents the photographs with chunky graphite liquid holding for 240 and 300mins observed by SEM, showing that chunky graphite was widely branched and interconnected in a network within each eutectic cell, which is in line with many other works [11,21,22]. The number of chunky graphite increases with increasing holding time and their morphologies change little.

Fig. 5 3-D morphology of spheroidal graphite

Fig. 6 SEM photo of quenched sample after different holding times

(a), (b) 240min and (c), (d)300min

4 Discussions

Through the whole observation, precipitation order of graphite at various stages of liquid holding is spheroidal, chunky, vermicular, and finally flake graphite. The liquid holding time has a great effect on the graphite morphology of ductile iron. Transition process of graphite morphology can be described as a function of holding time as shown in Fig.7. 060120180240300360420

1160

1200

124012801320

T e m p e r a t u r e ,℃Time,min

Spheroidal Spheroidal+Chunky Chunky+Vermicular Flake

Fig. 7 Relationship between graphite morphology and solidification history

Chemical composition and inoculation practice strongly influence the graphite morphology in ductile iron [21,23]. Undoubtedly, there is a general trend of decreasing residual Mg% or RE% with increasing hold time under the experimental conditions used in this study. The chemical composition of quenched specimen after holding for 240 min is 3.46C, 1.96Si, 0.16Mn, 0.011S, 0.023P, 0.005Ce, and 0.007Mg, without any Sb left(why ). Variation of element contents is small except spheroidizing elements amounts compared with initial chemical composition shown in Table 1. Generally speaking, the composition of cast iron is unlikely to be the only factor important in determining the graphite morphology [7,24]. However, for the same heat, after liquid holding the only difference that could be noted is shperoidizing elements concentration. In other words, the decreasing of nodulizing elements content promotes the transition of graphite morphology. Meanwhile, lack of effective inoculation with increasing holding time can contribute to transition of graphite morphology as well [21,22], contrary to I.Asenjo, et al [7] and Z.Ignaszak [22], who suggested that mould inoculation or post inoculation would increase nodule count, causing chunky graphite formation. Therefore the transition of graphite morphology can be attributed to the effect of different spheroidizing elements concentrations and lack of effective inoculation.

Normally, when the concentration of nodularizing elements in growth front is sufficient, graphite growth in a-axes is restricted and grows as spheroidal graphite. On the other hand, when concentration of nodularizing element is not sufficient to restrict growth in a-direction, vermicular graphite will grow [23,25,26]. However, in our experiment, that chunky graphite finally precipitates before vermicular graphite forms

was found. This observation is in agreement with that of R.K?llbom, et al[18], although the solidification process of cast iron seems to be completely reverse. They suggested that low local content of Mg would promote the chunky graphite formation and growth. However, they did not explain the reason why to form chunky graphite instead of vermicular graphite. In fact, vermicular graphite would form around chunky graphite as the holding time continues, indicating that chunky graphite will precipitate prior to vermicular, as shown in Fig. 3(g).

No chunky graphite connecting directly to large graphite nodule is observed. Ordinary both spheroidal and vermicular graphite could co-exist in the same regions with chunky graphite as shown in Fig. 3. They have no direct relationship each other on the formation process. Chunky graphite newly nucleates after the growth of spheroidal graphite almost stopped as verified above. Although chunky graphite can be easily found in heavy section ductile iron, in the present study, chunky graphite forms after liquid melt holding in the furnace for 240 min, where both content of spheroidizing elements and effective nucleus is insufficient. It does not meet the requirements of spheroidal graphite formation and causes graphite to branch frequently. Vermicular graphite forms subsequently. That is to say, the excessive content of spheroidizing elements is not exclusive reason for chunky graphite forming. These results are in direct contradiction with the observation by Shoji Kiguchi et al.[12,17] and Fang Keming et al[16], who reported chunky graphite is due to sufficient spheroidizing ability.

5 Conclusions

Based on the results obtained from the effect of holding time on the graphite morphology, the following conclusions can be made.

Transition process of graphite morphology is spheroidal, chunky, vermicular, and finally flake during liquid holding from 1320℃—1150℃within 7 hours. Chunky graphite precipitates directly during liquid holding as nodularizing ability is not sufficient. Vermicular graphite newly forms around chunky graphite eutectic cells. References

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《语言学纲要》名词解释_叶蜚声

《语言学纲要》名词解释导言 4.交际工具：人类交际活动所使用的工具。语言是人类最重要的交际工具。此外，身势等伴随动作是非语言的交际工具；旗语之类是建立在语言、文字基础上的辅助性交际工具；文字是建立在语言基础之上的一种最重要的辅助交际工具； 5.思维：是认识现实世界时的一种动脑筋的过程，也指动脑筋时进行比较、分析、综合以认识现实的能力。是人脑能动地反映客观现实的机能和过程。根据思维活动的不同形态可分为三种类型：直观动作思

维、形象思维、抽象思维。 6.社会：指生活在一个共同的地域中、说同一种语言、有共同的风俗习惯和文化习惯的人类社会的共同体，即一般所说的部落、部族和民族。与此相关联的现象就是社会现象。 7.社会现象：指那些与人类共同体的一切活动——产生、存在和发展密切联系的现象。取渐变，不能爆发突变。 8.语言发展的不平衡性：指语言结构体系发展变化是不平衡的，即词汇、语义、语音、语法的发展速度是不一样的。与社会联系最直接的词汇、语义变化最快，语音次之，语法最慢。 9.表层结构和深层结构：表层结构和深层结构相对，表层结构赋予句子以一定的语音形式，即通过语音形

式所表达出来的那种结构，表层结构是由深层结构转换而显现的；深层结构是赋予句子以一定的语义解释的那种结构。 10.组合关系：符号和符号组合起来的关系。符号和符号的组合形成语言的结构。 11.聚合关系：在链条的某一环节上能够相互替换的符号具有某种相同的作用，它们自然聚集成群。它们彼此的关系称为聚合关系。 23.音高：声音的高低，是由发音体形状及振动频率快慢决定的。 24.音重：声音的强弱，它取决于声波振幅的大小，而振幅的大小与发音时用力大小有关。 25.音质：也叫音色，指声音的品质或个性。

中国传媒大学语言学及应用语言学专业方向介绍

中国传媒大学语言学及应用语言学专业方向介绍（感谢凯程罗老师对本文的有益指导.) 语言学及应用语言学专业（050102） 1．应用语言学方向应用语言学方向是适应我国应用语言学发展需要设立的研究方向，它以“人机交际”和人际交际的语言理论和技能、技术为主要研究对象。作为跨学科的语言应用学科，它同人文科学、自然科学（数学、物理学、信息科学、计算机科学等）都有密切关系。本方向有社会语言学和计算语言学两个研究领域。社会语言学，重在研究语言在社会生活中的应用。它结合中国社会的文化背景，对语言应用进行多角度、全方位的研究，总结社会生活不同领域（如旅游、交通、商贸、公关、司法、教育等）人际交往中语言应用的特殊规律，对语言实践提供理论指导，并为我国语言文字规范化工作服务。计算语言学是利用计算机对人类自然语言处理和加工的科学，它是适应信息时代的要求而产生和发展起来的一门边缘交叉性学科。机器翻译、自然语言理解、语音识别与合成等都是本方向研究的重要课题，这些课题的研究对人工智能计算机的研制，起着举足轻重的作用。本方向将发挥中国传媒大学文、理、工多科院校、以及与教育部语言应用研究所合作的优势，为二十一世纪的应用语言学培养高层次专门人才。 2．对外汉语教学方向本研究方向以对外汉语教学研究为重点。汉语教学法历来都是汉语言基础理论体系中的重要组成部分，汉语教学法研究，也是汉语言基础理论研究中不可缺少的部分。自现代汉语诞生之日起，其教学过程即随之开始；应用语言学的产生和发展，更进一步推动了汉语教学研究的理论升华。特别是近几十年来，汉语教学研究，无论是对内的，还是对外的，都越来越受到重视。从建立完整的理论体系的角度说，我校有国内著名语言学家为学科带头人的现代汉语语法、修辞研究的深厚基础，最近又增添了应用语言学研究的雄厚实力，如果再加上汉语教学研究理论的参与，必将使汉语语言理论研究体系更趋完善。我校作为全国广播电视人才培养基地，多年来一直担负着为广播电视事业培养专门人才的重要任务。如何在汉语教学中把结构、意义和交际功能三者有机地结合起来，更好地培养学生实际运用语言的能力，也是多年来面临的理论与实际的大问题。随着时代要求的不断提高，矛盾日益突出。汉语教学如何借鉴心理学、教育学等相关学科的研究成果，结合语言应用实际，力求走出一条新路子。对外汉语教学专业人才的需求，近年来不断加大，国内各汉语教学机构为了在来华留学生的市场竞争中占有更多的份额，都纷纷把对外汉语教学高学历师资的竞争放到了首位。此外，全球性“汉语热”方兴未艾，特别是在进入新世纪之后，国内外汉语教学师资的需求量呈上升趋势。本方向将竭力培养对外汉语教学方面的高层次专门人才。 3. 语言信息处理方向语言信息处理是语言学与计算机科学交叉形成的一门新型学科，是应用语言学的重要组成部分。我国“十五”发展规划的重要方针之一，是大力推进信息化进程，以信息化带动工业化。

various approaches to morphology

Various Approaches to Morphology The grammatical description of many, if not all, languages is conveniently divided into two complementary sections: morphology and syntax. Morphology accounts for the internal structure of words. In linguistics, morphology is the identification, analysis and description, in a language, of the structure of morphemes and other linguistic units, such as words, affixes, parts of speech, intonation/stress, or implied context.It also explores the internal structure of words,and the rules by which words are formed.In this passage, I illstrate morphology in several aspects,from the inside formation , the rules of formation.and the main branches of morphology. Many people think of words as the basic meaningful elements of language ,many words can be broken down into still smaller units,called morphemes. Morphemes serve different purposes. Some derive new words by changing the meaning or the part of speech,others only refine and give extra grammatical information about the already existing meaning of a word. As morphemes are pairings of sounds with meanings,there are many complexiities involved, forming a new field by the mane morphophonology. Words could be analyzed into smaller components as they are formed by smaller units. Such as chairman,it is made up of chair and man ,words like boys ,checking ,and disappointment can likewise be further analyzed. They are each made up of boy and –s ,check and –ing ,and dis-. Appoint, and – ment. These smaller compoents are known as morphemes. But they themselves cannot be further analyzed. Chair could not be analyzed into ch and air .There are no relations between the parts ch ,air and the whole chair. Another example, the word ―unacceptability‖ can be divided into un-, accept, abil-, and -ity (abil- being a variant of -able). Of these, at least three are minimal grammatical units, in the sense that they cannot be analyzed into yet smaller grammatical units—un-, abil-, and ity. So morpheme is the smallest unit of language in terms of the relationship between expression and content, a unit that cannot be divided into further smaller units without destroying or drastically altering the meaning ,whether it is lexical or grammatical. Although I have mentioned above that morphemes are the smallest units of language in the certain situation. It self could be sub-classified into different types, depending on different criteria. (1)Free morpheme and bound morpheme An important concept in grammar and, more particularly, in morphology is that of free and bound forms. A bound form is one that cannot occur alone as a complete utterance (in some normal context of use). For example, -ing is bound in this sense, whereas wait is not, nor is waiting. Any form that is not bound is free.Those appear alone, or which may make up words by themselves ,are free morphemes, such as apple,open are free morphemes, or mono-morphemic words. And we could simply say that all mono-morphemic words are free morphemes. Moreover, poly-morphemic words, which consist wholly of free morphemes are called compound, such as headmaster, silkscalf. In contrast, -s in words , ad in adhere must appear with at least another morpheme are called bound morphemes. (2)Root ,affix and stem. We have met poly-morphemic words in the paragraphs mentioned above. In this section ,they ,other than compounds ,can be divided into roots and affixes. Root is the base form of a word that cannot be further be analyzed without destroying its meaning. In other words, it is that part of the word that is left when all the affixes are removed. While the affix is the collective term for the type of morpheme that can be used only when added

《语言学纲要》试题库剖析

绪论、第一章、第二章一、名词解释 1．语言学 2．语言 5．文言文 6．符号 7．符号形式 8．符号的任意性 9．语言符号 10．组合关系 11．聚合关系二、填空 1．__________、________ 、________________ 具有悠久的历史文化传统，是语言学的三大发源地。 2．__________ 是我国古代的书面语，用它写成的文章称为__________。 3．__________ 、__________ 、__________ 是我国传统的语文学。 4．研究语言的结构，主要是研究 __________、____________ 、__________ 三个部分。 5．运用语言传递信息的过程，可以分为________、________ 、_________ 、__________ 、__________ 五个阶段。 6．语言是人类社会的______________，而且也是思维的______________。 7．在一定条件下，身体姿势等伴随动作还可以离开语言独立完成交际任务。例如汉民族点头表示____________，摇头表示____________，送别时挥手表示 ______________，____________表示欢迎，咬牙切齿表示_____________，手舞足蹈表示____________。 8．人的大脑分左右两半球，大脑的半球控制语言活动，右半球掌管不需要语言的感性____________。 9．汉语的“哥哥”、“弟弟”，英语用________________表示，汉语的“舅舅、姨父、姑父、叔叔、伯伯”，英语用______________表示。 10．英语可以直接用数词修饰名词，汉语数词修饰名词一般要加上一个 _____。 11．儿童最早的智力活动就是学习_________。 12．任何符号，都是由和两个方面构成的。 13．一个符号，如果没有_______，就失去了存在的必要，如果没有_______，我们就无法感知，符号也就失去了存在的物质基础。 14．语言符号是_________和_________的统一体，声音是语言符号的______。

morphology的学习

Morphology refers to the study of the internal structure of words and the rules by which words are formed. Open class word and closed class word Open class words----content words of a language to which we can regularly add new words, such as nouns, adjectives, verbs and adverbs Closed class words---- grammatical or functional words, such as conjunction, articles, preposition and pronouns. Morpheme--the minimal unit of meaning词素 ---Words are composed of morphemes. Words may consist of one morpheme or more morphemes, e.g. 1-morpheme boy, desire 2-morpheme boy+ish, desir(e)+ble 3-morpheme boy+ish+ness, desir(e)+bl(e)+ity 4-morpheme gentle+man+li+ness, un+desir(e)+abl(e)+ity 5-morpheme un+gentle+man+li+ness 6-morpheme anti+dis+establish+ment+ari+an+ism 总的来说，形态学就是研究英语单词的语言学分支。英文介绍： Chapter 3 Morphology Morphology refers to the study of the internal structure of words and the rules by which words are formed. Open class word and closed class word Open class words----content words of a language to which we can regularly add new words, such as nouns, adjectives, verbs and adverbs Closed class words----grammatical or functional words, such as conjunction, articles, preposition and pronouns. Morpheme--the minimal unit of meaning ---Words are composed of morphemes. Words may consist of one morpheme or more morphemes, e.g. 1-morpheme boy, desire 2-morpheme boy+ish, desir(e)+ble 3-morpheme boy+ish+ness, desir(e)+bl(e)+ity 4-morpheme gentle+man+li+ness, un+desir(e)+abl(e)+ity 5-morpheme un+gentle+man+li+ness 6-morpheme anti+dis+establish+ment+ari+an+ism

语言学纲要名词解释.

语言学纲要名词解释导言 1.语言学：以语言作为专门研究对象的一门独立学科，其主要任务是研究语言的性质、结构和功能，通过考察语言及其应用的现象，来解释语言存在和发展的规律。 2.语文学：指19世纪历史比较语言学之前的语言研究，这时的语言研究尚未独立，语言学作为其他学科的附庸而存在，语言研究的主要目的是为了阅读古籍和语言教学，从而为统治者治理国家或为其他学科的研究服务。 3.小学：中国传统的语文学，由于汉语书面语使用的文字——汉字的特点，中国传统语言研究抓住汉字，分析它的形体，探求它的古代读音和意义，形成了统称“小学”的文字、音韵、训诂之学，也就是中国传统的语文学。 4.理论语言学：也称普通语言学，是关于语言的一般规律的理论研究。理论语言学的水平在很大程度上决定于具体语言学的研究成果。 5.共时语言学：以同时的、静态的分析方法，研究语言相对静止的状态，描写分析语言在某一时期、某一阶段的状况，是从横的方面研究语言。 6.历时语言学：研究语言发展的历史，观察一种语言的各个结构要素在不同发展阶段的历史演变，是从纵向的方面研究语言的历史。涉及到一种语言的叫做历时语言学，如历史语音学，历史词汇学，历史语法学等；涉及到多种语言和方言的叫做历史比较语言学。 7.索绪尔：瑞士语言学家，现代语言学的奠基人，结构主义语言学的开创者，著有《普通语言学教程》，被人们誉为“现代语言学之父”。他提出语言是符号体系；符号由能指所指两部分构成，这两部分的关系是任意的，一旦形成以后又是约定性的；符号系统内部存在“组合关系”和“聚合关系”；区分了“语言”和“言语”；“内部语言学”和“外部语言学”；“历时语言学”和“共时语言学”。他的学说标志着现代语言学的开始，在不同的程度上影响着20世纪的各个语言学派。 8.布龙菲尔德：美国描写语言学派的代表人物，它的主要贡献是将语言学从哲学理念建设成为一门科学。早期的著作是出版于1914年的《语言研究导论》，立足于心理学来阐释语言、刺激—反应论来解释语言的产生和理解的过程。1933年他的最有影响的著作《语言论》出版。这时，他已经从构造心理学转到行为心理学。他在该书中提出了美国结构语言学派研究语言的基本原则和描写语言结构的总框架。 9.乔姆斯基：转换生成语法的创始人，著有《句法结构》。最出他用结构主义的方法研究希伯来语，后来发现这种方法有很大的局限性，转而探索新的方法，逐步建立了转换生成语法，1957年出版的《句法结构》就是这一新方法的标志。这种分析方法风靡全世界，冲垮了结构语言学的支配地位，因而被人们成为“乔姆斯基革命”，对语言学的发展方向产成了巨大影响。 10.韩礼德：英国语言学家，功能主义语言学派的代表人物，继承了以弗斯为首的伦敦学派的基本理论，并吸收布拉格学派和哥本哈根学派的某些观点的基础上发展起来和创立了系统功能语法，著有《普通语言学教程》《语法功能论》等著作。他从人类学和社会学的角度出发研究语言与社会的关系，把语言看做“社会符号”，其包括功能系统、层次和语境等概念，在语法中认为系统中存在连锁系统和选择系统，在功能语法中他用功能的配置来解释语法结构，提出了概念功能、人际功能、语篇功能。20世纪70年代后，他将注意力转移到语言与社会学、符号学的关系上，对社会语言学进行研究。 11.赵元任：字宣仲，江苏常州人，生于天津。赵元任是“中国语言学之父”。他将科学运用于语言学研究的结果：用自然科学中的基本概念说明语言问题；用自然科学的先进成果记录和分析语音；把自然科学中的研究方法引入语言学；引入科学的描述事物的方式以及解决问题的程序等等。中国的传统语言学在他和同时代的一批学者的努力下，逐步走向现代化。 12.历史比较语言学：出现于18世纪末19世纪初，中心在德国。该学派采用历史比较的方法，通过语音和词形的比较研究语言的发展和演变，发现了语言之间的亲缘关系并建立了语言的谱系分类。历史比较语言学的兴起，是语言学成为一门独立的学科。经过一个多世纪的探索研究，弄清了世界上很多语言的同源关系，建立了世界语言的谱系分类，为语言学的发展做了很大贡献。历史比较语言学也有局限：他强调了语言的历史比较，忽视了语言的共时研究；孤立地研究语言单位，缺乏对语言系统性的研究。 13.结构主义语言学：1916年索绪尔的《普通语言学教程》标志着结构主义语言学的诞生。索绪尔语言理论的核心是语言是符号系统，突破了历史比较语言学的局限，开拓了语言研究的新领域，给语言学带来革命性的变化。

2010年中国传媒大学考博语言学理论试题及答案

中国传媒大学2010年攻读博士学位研究生入学考试语言学理论试题一.论述题。 1.必答题(40分) 就语言规划或语言规范化问题尽你所知进行论述。 2.选答题(30分,任选其一回答) A.就话语(也叫篇章、语篇)研究进行论述。 B.就形式主义语言学和功能主义语言学进行论述。二.分析题(30分,每小题10分) 1.指出下面三个四字格之间的联系,分析形成的原因,并说明各自的表达效果。喜鹊登枝喜上眉梢喜上眉梢 2.下面两组句子,一组可逆,一组不可逆,请从认知角度解释。我后悔死这件事了——这件事后悔死我了我后悔这件事了——★这件事后悔我了 3.运用预设理论解释下面句子。

北京又要打击非法一日游了中国传媒大学2010年攻读博士学位研究生入学考试语言学理论试题二.论述题。 1.必答题(40分) 就语言规划或语言规范化问题尽你所知进行论述。 (1)语言文字的合理发展,对一个国家或民族的发展具有不可估量的作用。国家或社会为了管理社会语言生活,对语言的现状及发展施加有计划有目的的影响以促进语言文字健康发展使其更好的尾社会服务而进行的各种工作就是语言规划。 (2)语言规划涉及的内容很多,主要包括民族共同语的确立和推广,民族共同语的规范和完善,语言选择,语言协调,语言调查,科技术语的统一和标准化,文字的创制和改革等。 (3)①语言文字立法是语言规划的一种体现。《中华人民共和国国家通用语言文字法》是语言政策的法律体现,对于加强语言文字工作有重要意义。②政府对语言的管理和影响表现在官方语言的选择上,外语教育也有语言选择问题,除了语言选择以外还有标准化问题,包括科技术语的标准化和语言规范化。 (4)语言规划的原则:语言规划必须尊重并且符合语言发展的客观规律,符合社会发展的需要,符合广大人民群众的意愿。避免两种倾向:一种是人在语言文字面前无能为力,无所作为;一种是过于夸大人的作用。

语言学纲要习题答案

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