3539 通用減速器機殼體側面銑削加工工藝裝備設計

3539 通用減速器機殼體側面銑削加工工藝裝備設計,通用,減速器,機殼,側面,銑削,加工,工藝,裝備,設備,設計 圖號 毛坯種類 鑄件名稱 通用減速機殼體 毛坯重量被加工 零件材料 HT200 硬度 HBS160~220工序名稱 通用減速機殼體連接孔鉆削加工 工序號 工時/min序號工步名稱工作行程/mm切速/（m·min -1）進給量/（mm·r -1）進給量/（mm·min -1）工進時間輔助時間1 裝卸工件 1.52 動力部件3 滑臺快進 47 6.3 0.00754 多軸向工進 73 0.06 500 20.41 1.225 滑臺快退 120 6.3 0.0196789累計 1.22 1.53單件總工時 2.75機床生產(chǎn)率 17.02件/h理論生產(chǎn)率 20.966件/h備注裝卸工件時間取決于操作者熟練程度，本機計算時取1.5min負荷率 81.4%產(chǎn)品型號 零件圖號 A0武漢理工大學華夏學院 機械加工工藝過程卡片 產(chǎn)品名稱 減速器 零件名稱 減速器箱體 共 4 頁 第 1 頁材 料 牌 號 HT200 毛 坯 種 類 金屬模機器造 型 毛坯外形尺寸 540×250×135 每 臺 件 數(shù) 備 注工 時 工序號工 名序 稱工 序 內(nèi) 容車間工段設 備 工 藝 裝 備準終 單件10 鑄造 以鑄造方式獲得工件毛坯 型腔20 時效處理30 檢驗 檢驗鑄件各部分尺寸 40 油漆底漆50 劃線，分 箱60 粗銑 粗銑兩箱結合面（上箱蓋以 12mm 上表面為基準，下箱體以 12mm 下表面為基準） X62W 游標卡尺、硬質合金端銑刀、專用夾具70 粗銑 粗銑上箱蓋頂面，下箱體下底面（以結合面為基準） X62W 游標卡尺、硬質合金端銑刀、專用夾具80 人工時效90 精銑 精銑結合面（上箱蓋以頂部為基準，下箱體以底面 為基準） X62W 游標卡尺、硬質合金端銑刀、專用夾具100 半精銑 半精銑上箱蓋頂部，下箱體底面（以結合面為基準） X62W 游標卡尺、硬質合金端銑刀、專用夾具110 合箱 按所劃線合箱120 鉆 鉆 M10 定位孔 組合鉆床 鉆頭、鉆套、專用夾具、游標卡尺130 攻絲 對 M10 定位孔攻絲至圖紙要求 組合鉆床 高速鋼機動絲錐、專用夾具設 計（日 期） 校 對（日期） 審 核（日期） 標準化（日期） 會 簽（日期）標記 處數(shù) 更改文件號 簽 字 日 期 標記 處數(shù) 更改文件號 簽 字 日 期產(chǎn)品型號 零件圖號 A0武漢理工大學華夏學院 機械加工工藝過程卡片 產(chǎn)品名稱 減速器 零件名稱 減速器箱蓋 共 4 頁 第 2 頁材 料 牌 號 HT200 毛 坯 種 類 金屬模機器造 型 毛坯外形尺寸 540×250×135 每 臺 件 數(shù) 備 注工 時 工序號工 名序 稱工 序 內(nèi) 容車間工段設 備 工 藝 裝 備準終 單件140 鉆 鉆 2×Φ8 錐銷孔 組合鉆床 高速鋼機動絲錐、專用夾具150 擴 擴 2×Φ8 錐銷孔 組合鉆床 擴孔刀、專用夾具、游標卡尺160 定位 在錐銷孔中打入定位銷170 鉸 鉸 2×Φ8 錐銷孔 組合鉆床 機鉸刀、專用夾具、游標卡尺180 鉆 鉆 8×Φ13 孔 組合鉆床 鉆頭、鉆套、專用夾具、游標卡尺190 锪 將 8×Φ13 孔锪平 Φ26 組合鉆床 锪孔刀、專用夾具200 鉆 鉆 4×Φ11 孔 組合鉆床 鉆頭、鉆套、專用夾具、游標卡尺210 锪 將 4×Φ11 孔锪平 Φ24 組合鉆床220 去毛刺230 拆箱240 清洗 清除機體結合面毛刺和切屑，重新裝配打入錐銷， 擰緊螺栓250 粗銑 粗銑軸孔端面 X62W 游標卡尺、硬質合金端銑刀、專用夾具260 精銑 精銑軸孔端面 X62W 游標卡尺、硬質合金端銑刀、專用夾具設 計（日 期） 校 對（日期） 審 核（日期） 標準化（日期） 會 簽（日期）標記 處數(shù) 更改文件號 簽 字 日 期 標記 處數(shù) 更改文件號 簽 字 日 期產(chǎn)品型號 零件圖號 A0武漢理工大學華夏學院 機械加工工藝過程卡片 產(chǎn)品名稱 減速器 零件名稱 減速器箱蓋 共 4 頁 第 3 頁材 料 牌 號 HT200 毛 坯 種 類 金屬模機器造 型 毛坯外形尺寸 540×250×135 每 臺 件 數(shù) 備 注工 時 工序號工 名序 稱工 序 內(nèi) 容車間工段設 備 工 藝 裝 備準終 單件270 粗鏜 粗鏜軸孔 組合鏜床 硬質合金鏜刀、鏜套、專用夾具、游標 卡尺280 精鏜 精鏜軸孔 組合鏜床 硬質合金鏜刀、鏜套、專用夾具、游標 卡尺290 鉆 鉆軸孔端面 36×Φ8 孔 組合鉆床 鉆頭、鉆套、專用夾具、游標卡尺300 鉸 鉸軸孔端面 36×Φ8 孔 組合鉆床 機鉸刀、專用夾具、游標卡尺310 攻絲 對軸孔端面 36×Φ8 孔攻絲至圖紙要求 組合鉆床 高速鋼機動絲錐、專用夾具320 鉆 鉆 2×Φ18 吊耳孔 組合鉆床 鉆頭、鉆套、專用夾具、游標卡尺330 鉆 鉆 6×Φ20 地腳螺栓孔 組合鉆床 鉆頭、鉆套、專用夾具、游標卡尺340 锪 將地腳螺栓孔锪平至圖紙要求 組合鉆床 锪孔刀、專用夾具350 鉆 鉆油塞、油尺孔 組合鉆床 鉆頭、鉆套、專用夾具、游標卡尺360 攻絲 對油塞、油尺孔攻絲至圖紙要求 組合鉆床 高速鋼機動絲錐、專用夾具370 锪 將油尺孔锪平至圖紙要求 組合鉆床 锪孔刀、專用夾具380 鉆 鉆 4×Φ6 通氣孔 組合鉆床 鉆頭、鉆套、專用夾具、游標卡尺390 攻絲 對 4×Φ6 通氣孔攻絲 4×Φ6 通氣孔 組合鉆床 高速鋼機動絲錐、專用夾具設 計（日 期） 校 對（日期） 審 核（日期） 標準化（日期） 會 簽（日期）標記 處數(shù) 更改文件號 簽 字 日 期 標記 處數(shù) 更改文件號 簽 字 日 期產(chǎn)品型號 零件圖號 A0武漢理工大學華夏學院 機械加工工藝過程卡片 產(chǎn)品名稱 減速器 零件名稱 減速器箱蓋 共 4 頁 第 4 頁材 料 牌 號 HT200 毛 坯 種 類 金屬模機器造 型 毛坯外形尺寸 540×250×135 每 臺 件 數(shù) 備 注工 時 工序號工 名序 稱工 序 內(nèi) 容車間工段設 備 工 藝 裝 備準終 單件400去毛刺，清晰，打標記410 檢驗設 計（日 期） 校 對（日期） 審 核（日期） 標準化（日期） 會 簽（日期）標記 處數(shù) 更改文件號 簽 字 日 期 標記 處數(shù) 更改文件號 簽 字 日 期學號 10110108404英語外文翻譯教 學 系： 機械制造及其自動化 指導教師： 齊洪方 專業(yè)班級： 機制 1084 學生姓名： 李笑軒 2012 年 5 月Machine design theory The machine design is through designs the new product or improves the old product to meet the human need the application technical science. It involves the project technology each domain, mainly studies the product the size, the shape and the detailed structure basic idea, but also must study the product the personnel which in aspect the and so on manufacture, sale and use question.Carries on each kind of machine design work to be usually called designs the personnel or machine design engineer. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineerig material, materials mechanics and machine manufacture technology has the deep elementary knowledge. If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly not necessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of productMust regard as the machine design is the machine design personnel carries on using creative ability the product design, the system analysis and a formulation product manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. The merely service data and the formula is insufficient to the completely decision which makes in a good design needs. On the other hand, should be earnest precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct design to turn wrongly.A good design personnel should dare to propose the new idea, moreover is willing to undertake the certain risk, when the new method is not suitable, use original method. Therefore, designs the personnel to have to have to have the patience, because spends the time and the endeavor certainly cannot guarantee brings successfully. A brand-new design, the request screen abandons obsoletely many, knows very well the method for the people. Because many person of conservativeness, does this certainly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not unified it after the confirmation new idea. Newly designs itself can have the question occurrence which many flaws and has not been able to expect, only has after these flaws and the question are solved, can manifest new goods come into the market the product superiority. Therefore, a performance superior product is born at the same time, also is following a higher risk. Should emphasize, if designs itself does not request to use the brand-new method, is not unnecessary merely for the goal which transform to use the new method. In the design preliminary stage, should allow to design the personnel fully to display the creativity, not each kind of restraint. Even if has had many impractical ideas, also can in the design early time, namely in front of the plan blueprint is corrected. Only then, only then does not send to stops up the innovation the mentality. Usually, must propose several sets of design proposals, then perform the comparison. Has the possibility very much in the plan which finally designated, has used certain not in plan some ideas which accepts. How does the psychologist frequently discuss causes the machine which the people adapts them to operate. Designs personnel''s basic responsibility is diligently causes the machine to adapt the people. This certainly is not an easy work, because certainly does not have to all people to say in fact all is the most superior operating area and the operating process. Another important question, project engineer must be able to carry on the exchange and the consultation with other concerned personnel. In the initial stage, designs the personnel to have to carry on the exchange and the consultation on the preliminary design with the administrative personnel, and is approved. This generally is through the oral discussion, the schematic diagram and the writing material carries on. In order to carry on the effective exchange, needs to solve the following problem: (1) designs whether this product truly does need for the people? Whether there is competitive ability (2) does this product compare with other companies'' existing similar products? (3) produces this kind of product is whether economical? (4) product service is whether convenient? (5) product whether there is sale? Whether may gain?Only has the time to be able to produce the correct answer to above question. But, the product design, the manufacture and the sale only can in carry on to the above question preliminary affirmation answer foundation in. Project engineer also should through the detail drawing and the assembly drawing, carries on the consultation together with the branch of manufacture to the finally design proposal.Usually, can have some problem in the manufacture process. Possibly can request to some components size or the common difference makes some changes, causes the components the production to change easily. But, in the project change must have to pass through designs the personnel to authorize, guaranteed cannot damage the product the function. Sometimes, when in front of product assembly or in the packing foreign shipment experiment only then discovers in the design some kind of flaw. These instances exactly showed the design is a dynamic process. Always has a better method to complete the design work, designs the personnel to be supposed unceasingly diligently, seeks these better method. Recent year, the engineerig material choice already appeared importantly. In addition, the choice process should be to the material continuously the unceasing again appraisal process. The new material unceasingly appears, but some original materials can obtain the quantity possibly can reduce. The environmental pollution, material recycling aspect and so on use, worker''s health and security frequently can attach the new limiting condition to the choice of material. In order to reduce the weight or saves the energy, possibly can request the use different material. Comes from domestic and international competition, to product service maintenance convenience request enhancement and customer''s aspect the and so on feedback pressure, can urge the people to carry on to the material reappraises. Because the material does not select when created the product responsibility lawsuit, has already had the profound influence. In addition, the material and between the material processing interdependence is already known by the people clearly. Therefore, in order to can and guarantees the quality in the reasonable cost under the premise to obtain satisfaction the result, project engineer makes engineers all to have earnestly carefully to choose, the determination and the use material. Makes any product the first step of work all is designs. Designs usually may divide into several explicit stages: (a) preliminary design; (b) functional design; (c) production design. In the preliminary design stage, the designer emphatically considered the product should have function. Usually must conceive and consider several plans, then decided this kind of thought is whether feasible; If is feasible, then should makes the further improvement to or several plans. In this stage, the question which only must consider about the choice of material is: Whether has the performance to conform to the request material to be possible to supply the choice; If no, whether has a bigger assurance all permits in the cost and the time in the limit develops one kind of new material.In the functional design and the engineering design stage, needs to make a practical feasible design. Must draw up the quite complete blueprint in this stage, chooses and determines each kind of components the material. Usually must make the prototype or the working model, and carries on the experiment to it, the appraisal product function, the reliability, the outward appearance and the service maintenance and so on. Although this kind of experiment possibly can indicate, enters in the product to the production base in front of, should replace certain materials, but, absolutely cannot this point take not earnestly chooses the material the excuse. Should unify the product the function, earnestly carefully considers the product the outward appearance, the cost and the reliability. Has the achievement very much the company when manufacture all prototypes, selects the material should the material which uses with its production in be same, and uses the similar manufacture technology as far as possible. Like this has the advantage very much to the company. The function complete prototype if cannot act according to the anticipated sales volume economically to make, or is prototypical and the official production installment has in the quality and the reliable aspect is very greatly different, then this kind of prototype does not have the great value. Project engineer is best can completely complete the material in this stage the analysis, the choice and the determination work, but is not remains it to the production design stage does. Because, is carries on in the production design stage material replacement by other people, these people are inferior to project engineer to the product all functions understanding. I n the production design stage, is should completely determine with the material related main question the material, causes them to adapt with the existing equipment, can use the existing equipment economically to carry on the processing, moreover the material quantity can quite be easy to guarantee the supply. In the manufacture process, inevitably can appear to uses the material to make some changes the situation. The experience indicated that, may use certain cheap materials to take the substitute. However, in the majority situation, in will carry on the production later to change the material to have in to start before the production to change the price which the material will spend to have to be higher than. Completes the choice of material work in the design stage, may avoid the most such situations. Started after the production manufacture to appear has been possible to supply the use the new material is replaces the material the most common reason. Certainly, these new materials possibly reduce the cost, the improvement product performance. But, must carry on the earnest appraisal to the new material, guarantees its all performance all to answer the purpose. Must remember that, the new material performance and the reliable very few pictures materials on hand such understood for the people. The majority of products expiration and the product accident caused by negligence case is because in selects the new material to take in front of substitution material, not truly understood their long-term operational performance causes. The product responsibility lawsuit forces designs the personnel and the company when the choice material, uses the best procedure. In the material process, five most common questions are: (a) did not understand or cannot use about the material application aspect most newly the best information paper; (b) has not been able to foresee and to consider the dusk year possible reasonable use (for example to have the possibility, designs the personnel also to be supposed further to forecast and the consideration because product application method not when creates consequence. ecent years many products responsibilities lawsuit case, because wrongly uses the plaintiff which the product receives the injury to accuse produces the factory, and wins the decision); (c) uses the material data not entire perhaps some data are indefinite, works as its long-term performance data is the like this time in particular; (d) the quality control method is not suitable and not after the confirmation; (e) the personnel which completely is not competent for the post by some chooses the material. Through to the above five questions analysis, may obtain these questions is does not have the sufficient reason existence the conclusion. May for avoid these questions to these questions research analyses the appearance indicating the direction. Although uses the best choice of material method not to be able to avoid having the product responsibility lawsuit, designs the personnel and the industry carries on the choice of material according to the suitable procedure, may greatly reduce the lawsuit the quantity. May see from the above discussion, the choice material people should to the material nature, the characteristic and the processing method have comprehensive and the basic understanding.機械設計理論機械設計是一門通過設計新產(chǎn)品或者改進老產(chǎn)品來滿足人類需求的應用技術科學。它涉及工程技術的各個領域，主要研究產(chǎn)品的尺寸、形狀和詳細結構的基本構思，還要研究產(chǎn)品在制造、銷售和使用等方面的問題。進行各種機械設計工作的人員通常被稱為設計人員或者機械設計工程師。機械設計是一項創(chuàng)造性的工作。設計工程師不僅在工作上要有創(chuàng)造性，還必須在機械制圖、運動學、工程材料、材料力學和機械制造工藝學等方面具有深厚的基礎知識。 如前所訴，機械設計的目的是生產(chǎn)能夠滿足人類需求的產(chǎn)品。發(fā)明、發(fā)現(xiàn)和科技知識本身并不一定能給人類帶來好處，只有當它們被應用在產(chǎn)品上才能產(chǎn)生效益。因而，應該認識到在一個特定的產(chǎn)品進行設計之前，必須先確定人們是否需要這種產(chǎn)品。應當把機械設計看成是機械設計人員運用創(chuàng)造性的才能進行產(chǎn)品設計、系統(tǒng)分析和制定產(chǎn)品的制造工藝學的一個良機。掌握工程基礎知識要比熟記一些數(shù)據(jù)和公式更為重要。僅僅使用數(shù)據(jù)和公式是不足以在一個好的設計中做出所需的全部決定的。另一方面，應該認真精確的進行所有運算。例如，即使將一個小數(shù)點的位置放錯，也會使正確的設計變成錯誤的。一個好的設計人員應該勇于提出新的想法，而且愿意承擔一定的風險，當新的方法不適用時，就使用原來的方法。因此，設計人員必須要有耐心，因為 所花費的時間和努力并不能保證帶來成功。一個全新的設計，要求屏棄許多陳舊的，為人們所熟知的方法。由于許多人墨守成規(guī)，這樣做并不是一件容易的事。一位機械設計師應該不斷地探索改進現(xiàn)有的產(chǎn)品的方法，在此過程中應該認真選擇原有的、經(jīng)過驗證的設計原理，將其與未經(jīng)過驗證的新觀念結合起來。新設計本身會有許多缺陷和未能預料的問題發(fā)生，只有當這些缺陷和問題被解決之后，才能體現(xiàn)出新產(chǎn)品的優(yōu)越性。因此，一個性能優(yōu)越的產(chǎn)品誕生的同時，也伴隨著較高的風險。應該強調的是，如果設計本身不要求采用全新的方法，就沒有必要僅僅為了變革的目的而采用新方法。在設計的初始階段，應該允許設計人員充分發(fā)揮創(chuàng)造性，不受各種約束。即使產(chǎn)生了許多不切實際的想法，也會在設計的早期，即繪制圖紙之前被改正掉。只有這樣，才不致于堵塞創(chuàng)新的思路。通常，要提出幾套設計方案，然后加以比較。很有可能在最后選定的方案中，采用了某些未被接受的方案中的一些想法。 心理學家經(jīng)常談論如何使人們適應他們所操作的機器。設計人員的基本職責是努力使機器來適應人們。這并不是一項容易的工作，因為實際上并不存在著一個對所有人來說都是最優(yōu)的操作范圍和操作過程。另一個重要問題，設計工程師必須能夠同其他有關人員進行交流和磋商。在開始階段，設計人員必須就初步設計同管理人員進行交流和磋商，并得到批準。這一般是通過口頭討論，草圖和文字材料進行的。為了進行有效的交流 ，需要解決下列問題：（1） 所設計的這個產(chǎn)品是否真正為人們所需要？（2） 此產(chǎn)品與其他公司的現(xiàn)有同類產(chǎn)品相比有無競爭能力？（3） 生產(chǎn)這種產(chǎn)品是否經(jīng)濟？（4） 產(chǎn)品的維修是否方便？（5） 產(chǎn)品有無銷路？是否可以盈利？ 只有時間能對上述問題給出正確答案。但是， 產(chǎn)品的設計、制造和銷售只能在對上述問題的初步肯定答案的基礎上進行。設計工程師還應該通過零件圖和裝配圖，與制造部門一起對最終設計方案進行磋商。通常 ，在制造過程中會出現(xiàn)某個問題?？赡軙髮δ硞€零件尺寸或公差作一些更改，使零件的生產(chǎn)變得容易。但是，工程上的更改必須要經(jīng)過設計人員批準，以保證不會損傷產(chǎn)品的功能。有時，在產(chǎn)品的裝配時或者裝箱外運前的試驗中才發(fā)現(xiàn)設計中的某種缺陷。這些事例恰好說明了設計是一個動態(tài)過程?？偸谴嬖谥玫姆椒▉硗瓿稍O計工作，設計人員應該不斷努力，尋找這些更好的方法。近些年來，工程材料的選擇已經(jīng)顯得重要。此外，選擇過程應該是一個對材料的連續(xù)不斷的重新評價過程。新材料不斷出現(xiàn)，而一些原有的材料的能夠獲得的數(shù)量可能會減少。環(huán)境污染、材料的回收利用、工人的健康及安全等方面經(jīng)常會對材料選擇附加新的限制條件。為了減輕重量或者節(jié)約能源，可能會要求使用不同的材料。來自國內(nèi)和國際競爭、對產(chǎn)品維修保養(yǎng)方便性要求的提高和顧客的反饋等方面的壓力，都會促使人們對材料進行重新評價。由于材料選用不當造成的產(chǎn)品責任訴訟，已經(jīng)產(chǎn)生了深刻的影響。此外，材料與材料加工之間的相互依賴關系已經(jīng)被人們認識得更清楚。因此，為了能在合理的成本和確保質量的前提下獲得滿意的結果，設計工程師的制造工程師都必須認真仔細地選擇、確定和使用材料。制造任何產(chǎn)品的第一步工作都是設計。設計通?？梢苑譃閹讉€明確的階段：（a）初步設計；（ b）功能設計；（ c）生產(chǎn)設計。在初步設計階段，設計者著重考慮產(chǎn)品應該具有的功能。通常要設想和考慮幾個方案，然后決定這種思想是否可行；如果可行，則應該對其中一個或幾個方案作進一步的改進。在此階段，關于材料選擇唯一要考慮的問題是：是否有性能符合要求的材料可供選擇；如果沒有的話，是否有較大的把握在成本和時間都允許的限度內(nèi)研制出一種新材料。在功能設計和工程設計階段，要做出一個切實可行的設計。在這個階段要繪制出相當完整的圖紙，選擇并確定各種零件的材料。通常要制造出樣機或者實物模型，并對其進行試驗，評價產(chǎn)品的功能、可靠性、外觀和維修保養(yǎng)性等。雖然這種試驗可能會表明，在產(chǎn)品進入到生產(chǎn)階段之前，應該更換某些材料，但是，絕對不能將這一點作為不認真選擇材料的借口。應該結合產(chǎn)品的功能，認真仔細地考慮產(chǎn)品的外觀、成本和可靠性。一個很有成就的公司在制造所有的樣機時，所選用的材料應該和其生產(chǎn)中使用的材料相同，并盡可能使用同樣的制造技術。這樣對公司是很有好處的。功能完備的樣機如果不能根據(jù)預期的銷售量經(jīng)濟地制造出來，或者是樣機與正式生產(chǎn)的裝置在質量和可靠性方面有很大不同，則這種樣機就沒有多大的價值。設計工程師最好能在這一階段完全完成材料的分析、選擇和確定工作，而不是將其留到生產(chǎn)設計階段去做。因為，在生產(chǎn)設計階段材料的更換是由其他人進行的，這些人對產(chǎn)品的所有功能的了解不如設計工程師。 在生產(chǎn)設計階段中，與材料有關的主要問題是應該把材料完全確定下來，使它們與現(xiàn)有的設備相適應，能夠利用現(xiàn)有設備經(jīng)濟地進行加工，而且材料的數(shù)量能夠比較容易保證供應。在制造過程中，不可避免地會出現(xiàn)對使用中的材料做一些更改的情況。經(jīng)驗表明，可采用某些便宜材料作為替代品。然而，在大多數(shù)情況下，在進行生產(chǎn)以后改換材料要比在開始生產(chǎn)前改換材料所花費的代價要高。在設計階段做好材料選擇工作，可以避免多數(shù)這樣的情況。在生產(chǎn)制造開始后出現(xiàn)了可供使用的新材料是更換材料的最常見的原因。當然，這些新材料可能降低成本、改進產(chǎn)品的性能。但是，必須對新材料進行認真的評價，以確保其所有性能都滿足要求。應當記住，新材料的性能和可靠性很少像現(xiàn)有材料那樣為人們所了解。大部分的產(chǎn)品失效和產(chǎn)品責任事故案件是由于在選用新材料作為替代材料之前，沒有真正了解它們的長期使用性能而引起的。產(chǎn)品的責任訴訟迫使設計人員和公司在選擇材料時，采用最好的程序。在材料過程中，五個最常見的問題為：（a）不了解或者不會使用關于材料應用方面的最新最好的信息資料；(b)未能預見和考慮擦黑年品可能的合理用途（如有可能，設計人員還應進一步預測和考慮由于產(chǎn)品使用方法不當造成的后果。在近年來的許多產(chǎn)品責任訴訟案件中，由于錯誤地使用產(chǎn)品而受到傷害的原告控告生產(chǎn)廠家，并且贏得判決）；(c)所使用的材料的數(shù)據(jù)不全或是有些數(shù)據(jù)不確定，尤其是當其長期性能數(shù)據(jù)是如此的時候；(d)質量控制方法不適當和未經(jīng)驗證；(e)由一些完全不稱職的人員選擇材料。通過對上述五個問題的分析，可以得出這些問題是沒有充分理由存在的結論。對這些問題的研究分析可以為避免這些問題的出現(xiàn)指明方向。盡管采用最好的材料選擇方法也不能避免發(fā)生產(chǎn)品責任訴訟，設計人員和工業(yè)界按照適當?shù)某绦蜻M行材料選擇，可以大大減少訴訟的數(shù)量。從以上的討論可以看出，選擇材料的人們應該對材料的性質，特點和加工方法有一個全面而基本的了解。