1270418 九、發明說明： 【發明所屬之技術領域】 本發明係關於一種用於3 C產業、運輸交通產 5業及運動器材結構的高強度鎂合金，結合往復式 擠型法將以往難擠型的高鋁含量鎂合金在擠型筒 中鍛鍊成均質、均勻、細晶、細相的緻密微結構， 進而獲得輕量化、低成本、高強度、高塑性成形 能力的鎂合金完整擠型材 10 【先前技術】 由於3C產業的蓬勃發展及隨身資訊產品輕量化的潮 流’近年來鎭合金已成為資訊產品中最具應用潛力的外殼 15 20 及内構件i屬，除筆§己型電腦外殼帶動使用的風潮外，鎂 合金在手機、PDA、數位相機及交通運輸工具、運動器材 的應用上亦有增加之趨勢，尤其是汽車結構性零件的鎂合 金用量近年來更大幅提升。 鎂合金為六方最密堆積結構（hcp )，滑移系統只有 3個使其塑性變形自由度大幅受限，在低溫下不具有良 好的加工性，因此目前鎮合金大多使用冷室、熱室壓鑄及 ㈣f鑄造方式生產’只有少量鎂合金採用鍛造、滾軋和 松3L等方法W造。為了增加鎂合金的應用範圍，首要便是 良好的塑性加工製程並保有其強度③度優勢，因此目 如有許多研究集中在鈿曰έ 曰钟摄沾π人入、、，日日、、、σ構鎂合金的開發，因為具備細 曰曰口 、、口至不但可以有效提升室溫的強度及延性，而 且可大幅改進超塑性及&刑w ρ 、丨王而 r生及成型性。另一方面，也可利用 25 1270418 設計，在鎂合金中添加A1、Zn、Υ、Ga、RE等元素來增 加室溫強度。 晶粒細化的製程，除了快速凝固加粉末冶金（rapid solidification processing plus powder metallurgy)、熱機處 5 理（thermo-mechanical processing )及機械合金加粉末冶 金(mechanical alloying plus powder metallurgy)夕卜，近年 來更開發累積應變法（accumulative strain method)達到晶 粒細化的目的，例如Valiev等人提出的扭轉應變法（torsion straining )及Segal等人提出的等通道轉角擠型法（equal 10 channel angular extrusion )，主要是在低溫下對合金施以反 覆塑性變形，累積高密度差排，並使低角度晶界逐漸轉變 為高角度晶界達到細化晶粒的效果。而本發明創作人亦開 發獨特的往復式擠型法（reciprocating extrusion)，如中華 民國發明專利第71320號、美國專利5571348、曰本特許 15 第2640642號及中國大陸發明專利ZL 95 1 07603.5所揭 示，即在再結晶溫度附近對合金施以來回擠型，利用破碎 效應（fragmentation effect)、累積動態再結晶（accumulated dynamic recrystallization)及塑性流（plastic flow)混練的綜 合效應，使合金的第二相及晶粒達到細化及均勻化的效 20 果，並因而提升材料特性。 由於等通道轉角擠型及往復式擠型法皆可在固態狀 態下直接使塊材合金獲得細晶粒，有利於厚件的加工成型 及超塑性並使強度及延性增加，所以兩種製程皆深具潛力 開發高性能合金。但是由於操作溫度較高，往復式擠型不 25 但較能夠處理大尺寸的塊材合金，而且其細晶結構較穩定 1270418 且均向（lsoiropic)’所以在實用面上此法將更適合鎂合金塊 材細晶化的操作及性能的提升。 AZ系列鎂合金由於含成本較低的鋁元素且較易擠 型，所以屬於應用最廣的系列，其中以鋁含量達8 wt% 5的AZ80鎂合金最強，典型的降伏強度為25〇 ，抗拉 強度為340 MPa，伸長率達7%，但由於β相（Mgi7Ai^含 量太高且粗化，擠型時易破裂的緣故，8 ^%鋁含量的az8〇 鎂合金已屬不易擠型的合金，因此再提高鋁含量已不是適 當的合金設計，8wt%鋁含量幾乎已是鎂合金鑄錠能施以 10擠鍛製程的上限。Daloz利用快速凝固法製作不同鋁含量 (8〜20%A1)的粉末再施以擠型，雖然可細化β相，增進擠 型旎力，但其結論是Α1含量不應超過丨5 at%，否則伸長 里更低更脆，當紹含量為15.6 wt%時，降伏強度為381 MPa，抗拉強度為434 MPa，伸長率為2·5%。此外，以快 15速/旋固法製作鎂合金粉末，本質上不但成本高、步驟繁複， 而且鎂粉容易燃燒，操作上更增加成本及危險，所以極難 有商業上的競爭力及應用價值。因此如何以適當的低成本 製程配合高鋁含量的添加自然成為一項重要的課題。 20 【發明内容】 本發明提供一種咼強度鎂合金之製造方法，其包括： (1)提供一鎂合金材料，其主要成分包含：（a)鎂，其重量比 為66.0〜89.5% ; (b)鋁，其重量比為100〜30 0% ;及（c) 鋅，其重量比為0.5〜4.0% ;以及（2)將該鎂合金加熱軟化， 25 並施以往復擠壓。 本發明步驟（2)之擠壓係直至該鎂合金之總平均晶粒 1270418 小於10//m者。該步驟（2)之擠壓方式，並無須特殊限制， 只要擠壓直至該鎂合金之總平均晶粒小於1〇#m即可以。 例如使用往復式擠型機往復擠壓，直至該鎂合金之總平均 晶粒小於1 〇 # m者。 5 本發明之前述製造方法，更可以包括步驟（3)將該鎂 合金經以退火熱處理者。 【實施方式】 關於本發明之製造方法中，將該鎂合金加熱軟化並施 1〇以擠壓之製程，係以往復式擠型機往復擠壓。由於往復式 擠型法係在密閉的擠筒中來回擠型，不會有擠型破裂的顧 慮，同時可避免快速凝固及粉末冶金的費時、高成本及危 險，所以本發明即利用往復式擠型法克服添加便宜強化元 素A1的缺點：即大量且粗大的β相Μ^7Α1ΐ2使合金鑄錠 15極硬脆，不易進行塑性加工。進而使此材料能輕易的製成 擠型件。此外，往復式擠型法更提升此合金性能的改進， 不但可使β相及第二相細化並均勻散佈於細晶的基材相 中，獲得適當延展性，而且可大幅提升合金強度及耐蝕性， 更使得合金在適當溫度時，得到極佳的高速超塑成型能 2〇力。換言之，本發明的目的係利用往復式擠型法及高鋁含 量的綜合優點開發輕量化、低成本、高強度、高塑性成形 旎力及更耐蝕的鎂合金，以擴展鎂合金的應用面。 關於本發明之咼強度鎂合金，其主要成分包含：（a) 鎂，其重量比為66.0〜89.5% ; (b)鋁，其重量比為1〇〇 25〜30·0% ’及（c)鋅’其重量比為〇·5〜4〇%。本發明之高 強度鎮合金，亦可以添加其他之金屬。 1270418 為使本發明之技術思想更具體化，乃以實驗加以證 明，以下實施例即說明此一技術思想是正確的。 實施例： 5 1.材料準備及成分分析 所使用的材料是利用氣氛保護熔煉爐熔解鑄造，在爐 口設置氣氛保護管路，通以乾燥空氣+〇.〇3%SF6作為熔湯 保護，先將熔煉爐加熱至750 °C，然後將純鎂置入爐中熔 解，再將已經計算好比例之純鋁及純辞成分加入鎂熔湯中 10 並作適度攪拌，而後在680 t利用湯杓將熔湯倒入模穴為 直徑40.3 mm、深154 mm的預熱鑄模中。不同成分鑄錠 經採樣後利用ICP-AES作成分分析，結果如表1所示。最 後將鑄錠車削加工成為直徑34 mm、長120 mm之擠型錠， 以符合擠型機的擠筒内腔的尺寸。 15 表1實施例鎂合金之組成（wt%) 合金 A1 Zn Mn Fe Cu Ni Mg Mg-10Al-lZn 10.1 1.0 0.0082 0.0040 0.2312 0.0019 Bal. Mg-15Al-lZn 15.0 1.0 0.0084 0.0218 0.0020 0.0015 Bal. Mg-20Al-lZn 18.9 1.1 0.1700 0.0040 0.0150 0.0010 Bal. Mg-25Al-lZn 24.0 1.0 0.0108 0.0369 0.0029 0.0013 Bal. Mg-28Al-4Zn 28.8 4.1 0.0092 0.0671 0.0027 0.0045 Bal. 1270418 2.往復式擠型 往復式擠型之基本操作示意圖如圖1所示，1主要社 構為兩組對稱的擠型筒及擠桿，擠旋腔直徑36_、長^ _ ’在兩個擠型筒中央置有—擠型模，模孔直徑^ 12 5 mm，擠型比為9 : 1。 首先將擠型筒及擠型模加溫到所需之擠型溫度，同時 將擠錠置於怪溫爐中以相同溫度預熱。第一次擠型時先將 播桿B推進錠料至擠型模，而後利用擠桿A向左施壓，使 錠料通過擠型模孔而壓到擠桿B，此時擠桿B因受擠料推 10動向左同步退後，並因而使擠料受背壓而膨脹填滿擠筒， 擠桿A抵達擠型模後，進行反向的第2次擠型，使錠料又 回到右邊擠型筒内，如此重複上述動作直至所需的擠型次 數為止，在最後一次擠型時則退去一端之擠桿，如圖1(e) 所示，經由另一邊的擠桿施壓將擠好的錠料通過模孔擠成 15直徑12 mm的條棒；另外也可以設計最後一次同進退擠型 將錠料留置於右半側擠型筒中，然後將模具分離則可以得 到直徑36mm的大塊細晶材料。本實施例的擠型溫度為325 及350°C，擠型次數為10次，最後擠成直徑12nim的條棒。 20 3 ·金相觀察 將各成分鑄錠及各個擠型條件擠製的條棒切割成適當 大小的試片依序用 # 240、# 400、# 800、# 1200、# 4000 的SiC砂紙研磨後，利用3μιη及Ιμπι鑽石懸浮液拋光，鑄 錠試片採用磷酸浸蝕液（90%酒精+ 10%磷酸）浸蝕 25 1 〇秒’而擠型後的試片則利用苦味酸浸餘液（3 5 ml酒精 + 5 ml水+ 2.1 g苦味酸+ 5ml醋酸）浸蝕5秒，然後 10 1270418 利用光學顯微鏡（OM )及JEOL JSM-5410掃描式電子顯 > 微鏡（SEM )以觀察鑄造狀態及擠型後的微結構。 . 4·硬度測量 . 5 將各成分鑄錠及各個擠型條件擠製的條棒切割成適當 _ 大小的硬度測試試片，依序用# 240、# 400、# 8〇〇、# 12⑻、 # 4000的SiC砂紙研磨後，再以維氏硬度機測量硬度值， 取六點做平均值。 10 5 ·常溫拉伸試驗 € 常溫拉伸試棒尺寸的標距長度為25 mm，標距直徑為 6·25 mm，拉伸試驗機為Instron45〇5。試棒的拉伸方向平 行於擠型方向，拉伸速率為1 ·2 mm/min，並取部分試片置 Μ = 40〇°C持溫0.5小時水淬後（退火處理）再進行常溫拉伸測 6·重量損失測試 。將325〇C擠型試棒加工成尺寸φ = 1〇瓜瓜、匕=7瓜爪 2圓柱狀試片，然後浸泡在3 wt%鹽水中進行腐㈣試， φ 浸泡後經過Cr〇3+ AgN〇3 + Ba(N〇3)2水溶液浸泡以去除 20表面氧化物，秤其最後重量並統計重量損失。 7 ·微結構及性質改進 由不同成份鎂合金鑄造狀態的SEM及〇M照片，可發 «微結構為等轴樹枝晶相及樹枝間相所構成’，、、由於^ - 5時的流速及凝固速率較快，樹枝晶趨向等轴狀，且可發現 有些樹枝晶間有非圓形的孔洞，為固化時的微縮孔:在 11 1270418 SEM中可發現鑄錠㈣含量愈高，所產生的㈣間相愈多 並呈共晶’經由EPMA分析證實共晶中較白的相即為 Mg-Al相圖437。(：共晶反應所產生的β # ,成份為 MgnAl〗2,當Α1含量28糾％及Ζη含量為4心時，樹枝 5相變成β相，樹枝間相除共晶α+β外，尚有白色的富a 相’因此高Ζη含量使28wt%A1含量成為過共晶成份，並 有MgZn相在最後的晶界形成。 這二不同銘鋅έ畺的鎮合金鑄錠經由十次擠型都能獲 得光亮完整且無表面裂痕的擠型材，顯示此些難以由禱^ 10狀態直接擠型成功的鎂合金，都能經由多次往復式擠型轉 換成易擠型的材質，並得到擠件。 經由微結構比較，可看出往復式擠型不但破壞了鑄造 、。構及缺而且取而代之的獲得了相當緻密均質且再結晶 的鍛造結構。例如含~愈多的合金含Μ鳥的β相愈 15粗且愈多，但往復式擠型可使β相碎裂細化而且分散於基 地中呈均勻分佈。 根據橫截面採用截線法可求得平均晶粒尺寸： d = L/ (ΜΝ) ” :d為θ日粒平均尺寸’ L是截線長度，μ是放大倍率， 20 Ν是被截線所穿過的晶界數目。圖2為以及@相的晶粒尺 寸而圖3為總平均晶粒尺寸，可知在此兩種擠型溫度下， 口、’ 3里的鎂a金可獲得約丨〇 以下的細小晶粒，此對 強度伸長里、超塑性及抗蝕性都具提升的作用。 '的度低，是可用結構金屬中最輕的金屬，本發明 25的合金設計加入A1含量約10〜28wt%，以更多的β相增 12 1270418 政佈強化的效果’但對鎂合金本身的密度僅做小量的提 升，仍保留了鎂合金密度低的優勢。此由表2所列的實測 值，可以發現增加比率並不多，最高僅16·8%。另一方面， ，4顯示銘的添加由1G增加到28赠％時，無論是禱造或 疋才月里狀L，硬度皆呈大幅的提升，鑄造狀態由π s 6〇 增至180，擠型由Η" 8〇增至2〇〇，由此也可看出擠型 硬度比鑄錠硬度都提升20 %以上。 、表3為不同鋁鋅含量鎂合金的拉伸性質，可看出降 ㈣度隨I呂含量的提升而提升，其強度及伸長量組合明 j的k於壓鑄鎂合金AZ91D，雖然伸長率隨鋁含量有下 牛見象反映了 β相強化的相反影響，但仍不失往復式擠 型法仍能對此類合金做出完整無裂痕擠型件的特色，使 那些：鋁含量伸長量趨於零的鎂合金至少能用在壓縮應 力狀態的零組件及結構件用途，而發揮輕質高強的特 15 =。而本實施例得到較廣的強度及伸長量組合也是一項 垃點，即透過不同的鋁含量及熱處理可提供應用上較多 元的選擇。 表2貫施例鎂合金經325。(：往復式擠型十次後的密度，並1270418 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to a high-strength magnesium alloy for use in the 3 C industry, the transportation and transportation industry, and the structure of sports equipment, and the reciprocating extrusion method is used in the past. The high-aluminum content magnesium alloy is drilled into a compact, homogeneous, fine-grained, fine-phase dense microstructure in a squeeze cylinder, thereby obtaining a magnesium alloy complete extruded profile with light weight, low cost, high strength and high plastic forming ability. Technology] Due to the booming development of the 3C industry and the trend of lightweight information on portable information products, in recent years, niobium alloy has become the most promising shell 15 20 and internal component i of information products, in addition to the pen § computer casing In addition to the trend, magnesium alloys have also increased in the use of mobile phones, PDAs, digital cameras and transportation vehicles, sports equipment, especially the use of magnesium alloys in structural parts of automobiles has increased significantly in recent years. The magnesium alloy is the hexagonal closest packed structure (hcp), and only three of the slipping systems have greatly limited the plastic deformation freedom, and have no good processability at low temperatures. Therefore, most of the current alloys use cold chamber and hot chamber die casting. And (4) f casting method production 'only a small amount of magnesium alloy is made by forging, rolling and loose 3L. In order to increase the application range of magnesium alloys, the first is a good plastic processing process and retains its strength of 3 degrees. Therefore, many studies focus on 钿曰έ 曰 摄 沾 π 人 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 The development of σ-magnesium alloys, because of its fine mouth and mouth, can not only effectively improve the strength and ductility of the room temperature, but also greatly improve the superplasticity and the singularity and the formability. On the other hand, it is also possible to use the 25 1270418 design to add elements such as A1, Zn, yttrium, Ga, and RE to the magnesium alloy to increase the room temperature strength. The process of grain refinement, in addition to rapid solidification processing plus powder metallurgy, thermo-mechanical processing, and mechanical alloying plus powder metallurgy, in recent years The accumulative strain method has been developed to achieve grain refinement, such as the torssion straining proposed by Valiev et al. and the equal 10 channel angular extrusion proposed by Segal et al. It mainly applies repeated plastic deformation to the alloy at low temperature, accumulates high-density difference rows, and gradually transforms low-angle grain boundaries into high-angle grain boundaries to achieve grain refinement. The creators of the present invention have also developed a unique reciprocating extrusion method, such as the Republic of China Invention Patent No. 71320, U.S. Patent 5,571,348, Sakamoto No. 15 No. 2640642, and Chinese Mainland Patent No. ZL 95 1 07603.5. That is, the alloy is subjected to a back-and-forthing type near the recrystallization temperature, and the second phase of the alloy is made by the combined effect of a fragmentation effect, an accumulated dynamic recrystallization, and a plastic flow kneading. And the grain is refined and homogenized, and thus the material properties are improved. Since the equal channel corner extrusion and the reciprocating extrusion method can directly obtain the fine grain of the bulk alloy in the solid state, which is advantageous for the processing and superplasticity of the thick parts and the increase of the strength and the ductility, both processes are Deep potential to develop high performance alloys. However, due to the higher operating temperature, the reciprocating extrusion type is not 25 but it is more capable of handling large-sized bulk alloys, and its fine-grained structure is stable 1270418 and uniform (lsoiropic). Therefore, this method will be more suitable for magnesium on practical surfaces. The operation and performance improvement of the fine crystallization of the alloy block. AZ series magnesium alloy is the most widely used series because it contains low cost aluminum element and is easy to squeeze. Among them, AZ80 magnesium alloy with aluminum content of 8 wt% 5 is the strongest, and the typical drop strength is 25〇. The tensile strength is 340 MPa and the elongation is 7%. However, due to the β phase (Mgi7Ai^ content is too high and coarse, the extrusion is susceptible to cracking, 8^% aluminum content of az8 bismuth magnesium alloy is not easy to squeeze. Alloys, so increasing the aluminum content is not a proper alloy design. The 8wt% aluminum content is almost the upper limit of the 10 extrusion process for magnesium alloy ingots. Daloz uses the rapid solidification method to make different aluminum content (8~20%A1). The powder is applied to the extrusion type. Although the β phase can be refined to improve the extrusion force, the conclusion is that the Α1 content should not exceed 丨5 at%, otherwise the elongation is lower and more brittle, and the content is 15.6 wt. When the % is decreased, the tensile strength is 381 MPa, the tensile strength is 434 MPa, and the elongation is 2.5%. In addition, the magnesium alloy powder is prepared by the fast 15 speed/rotation method, which is not only costly, complicated, and magnesium. The powder is easy to burn, and the operation increases the cost and danger, so it is extremely difficult to have a business. The competitiveness and application value of the product. Therefore, how to mix the high aluminum content with an appropriate low-cost process naturally becomes an important issue. 20 SUMMARY OF THE INVENTION The present invention provides a method for producing a barium-strength magnesium alloy, which comprises: (1) Providing a magnesium alloy material whose main component comprises: (a) magnesium in a weight ratio of 66.0 to 89.5%; (b) aluminum in a weight ratio of 100 to 30%; and (c) zinc, The weight ratio is 0.5 to 4.0%; and (2) the magnesium alloy is heated and softened, 25 and subjected to reciprocating extrusion. The extrusion of the step (2) of the present invention until the total average grain size of the magnesium alloy is 1270418 is less than 10/ /m. The extrusion method of the step (2) is not particularly limited as long as the extrusion until the total average grain size of the magnesium alloy is less than 1 〇 #m. For example, reciprocating extrusion using a reciprocating extruder, Until the total average grain size of the magnesium alloy is less than 1 〇 #m. 5 The foregoing manufacturing method of the present invention may further comprise the step (3) of subjecting the magnesium alloy to annealing heat treatment. [Embodiment] Regarding the manufacture of the present invention In the method, the magnesium alloy is heated and softened and applied 1〇 In the extrusion process, the reciprocating extrusion machine is used for reciprocating extrusion. Since the reciprocating extrusion method is extruded back and forth in a closed extrusion tube, there is no concern of extrusion fracture, and rapid solidification and powder metallurgy can be avoided. The invention is time-consuming, high-cost and dangerous, so the invention overcomes the disadvantage of adding the cheap strengthening element A1 by using the reciprocating extrusion method: that is, the large and coarse β phase Μ^7Α1ΐ2 makes the alloy ingot 15 extremely hard and brittle, and is not easy to be plastically processed. In turn, the material can be easily made into extruded parts. In addition, the reciprocating extrusion method improves the performance of the alloy, and the β phase and the second phase can be refined and evenly dispersed in the fine crystal substrate phase. In the middle, the proper ductility is obtained, and the strength and corrosion resistance of the alloy can be greatly improved, and the alloy can obtain excellent high-speed superplastic forming energy at a suitable temperature. In other words, the object of the present invention is to develop a lightweight, low cost, high strength, high plastic forming force and a more corrosion resistant magnesium alloy by utilizing the advantages of the reciprocating extrusion method and the high aluminum content to expand the application surface of the magnesium alloy. Regarding the bismuth strength magnesium alloy of the present invention, the main component thereof comprises: (a) magnesium in a weight ratio of 66.0 to 89.5%; (b) aluminum in a weight ratio of 1 〇〇 25 to 30·0% ' and (c) Zinc's weight ratio is 〇·5~4〇%. The high strength town alloy of the present invention may also be added with other metals. 1270418 In order to make the technical idea of the present invention more specific, it is proved by experiments that the following embodiment explains that this technical idea is correct. Examples: 5 1. Material preparation and composition analysis The materials used are melt-casting by atmosphere protection smelting furnace, and atmosphere protection pipeline is set at the furnace mouth. Dry air + 〇.〇3%SF6 is used as melt protection. The smelting furnace is heated to 750 ° C, then the pure magnesium is placed in the furnace to be melted, and the calculated proportion of pure aluminum and pure components are added to the magnesium melt soup 10 and moderately stirred, and then used in 680 t The molten soup was poured into a preheating mold having a diameter of 40.3 mm and a depth of 154 mm. Ingots with different compositions were sampled and analyzed by ICP-AES. The results are shown in Table 1. Finally, the ingot is turned into an extruded ingot of 34 mm in diameter and 120 mm in length to meet the size of the inner cavity of the extruder. 15 Table 1 Example Magnesium alloy composition (wt%) Alloy A1 Zn Mn Fe Cu Ni Mg Mg-10Al-lZn 10.1 1.0 0.0082 0.0040 0.2312 0.0019 Bal. Mg-15Al-lZn 15.0 1.0 0.0084 0.0218 0.0020 0.0015 Bal. Mg-20Al -lZn 18.9 1.1 0.1700 0.0040 0.0150 0.0010 Bal. Mg-25Al-lZn 24.0 1.0 0.0108 0.0369 0.0029 0.0013 Bal. Mg-28Al-4Zn 28.8 4.1 0.0092 0.0671 0.0027 0.0045 Bal. 1270418 2. Basic operation of reciprocating extruded reciprocating extrusion The schematic diagram is shown in Figure 1. The main structure is two sets of symmetrical extrusion cylinders and squeeze rods. The diameter of the extrusion chamber is 36_, and the length of the extrusion chamber is placed in the center of the two extrusion cylinders. ^ 12 5 mm, extrusion ratio is 9: 1. The extrusion barrel and the extrusion die are first warmed to the desired extrusion temperature while the ingot is placed in a strange temperature furnace to preheat at the same temperature. When the first extrusion type, the propeller B is first pushed into the extrusion mold, and then the extrusion rod A is pressed to the left, so that the ingot is pressed to the extrusion rod B through the extrusion die hole, and at this time, the extrusion rod B is pressed. The squeezed material pushes the movement to the left and then retreats to the left, and thus the squeezed material is expanded by the back pressure to fill the squeeze tube. After the squeeze rod A reaches the extrusion die, the second extrusion type is reversed, so that the ingot is returned again. To the right extrusion barrel, repeat the above action until the required number of extrusions. At the last extrusion, the extrusion rod at one end is removed, as shown in Figure 1(e), and pressed through the other side of the extrusion rod. The extruded ingot is extruded through a die hole into a 15 mm diameter bar; in addition, the last in-line decompression type can be designed to leave the ingot in the right half extrusion barrel, and then the mold is separated to obtain a diameter of 36 mm. Large pieces of fine-grained material. The extrusion temperature of this embodiment was 325 and 350 ° C, the number of extrusions was 10, and finally the bar was extruded into a diameter of 12 nm. 20 3 · Metallographic observation After cutting the ingots of each component and the extruded bars, the test pieces of appropriate size were sequentially ground with #240, #400, #800, #1200, #4000 SiC sandpaper. Polished with 3μιη and Ιμπι diamond suspensions, the ingot test piece is etched with phosphoric acid etching solution (90% alcohol + 10% phosphoric acid) for 25 1 〇 second', and the extruded test piece uses bitter acid leaching solution (3 5 Mol alcohol + 5 ml water + 2.1 g picric acid + 5 ml acetic acid) etched for 5 seconds, then 10 1270418 using optical microscopy (OM) and JEOL JSM-5410 scanning electron display > micromirror (SEM) to observe the casting state and squeeze The microstructure after the type. 4. Hardness measurement. 5 Cut the ingots of each component and the extruded bars of each extrusion condition into hardness test pieces of appropriate size, using #240, #400, #8〇〇, #12(8), After the # 4000 SiC sandpaper was ground, the hardness value was measured by a Vickers hardness machine, and six points were taken as an average value. 10 5 · Normal temperature tensile test. The gauge length of the normal temperature tensile test bar is 25 mm, the gauge length is 6·25 mm, and the tensile tester is Instron 45〇5. The tensile direction of the test bar is parallel to the extrusion direction, the stretching rate is 1 · 2 mm / min, and part of the test piece is placed at 〇 = 40 〇 ° C for 0.5 hour after water quenching (annealing treatment) and then normal temperature drawing Stretching test 6. Weight loss test. The 325〇C extruded test bar was processed into a cylindrical test piece of size φ = 1 〇 melon, 匕 = 7 melon 2, and then immersed in 3 wt% saline for rot (4) test, φ immersed after Cr 〇 3+ An aqueous solution of AgN〇3 + Ba(N〇3) 2 was immersed to remove 20 surface oxides, the final weight was weighed and the weight loss was counted. 7 · Microstructure and properties improvement SEM and 〇M photographs of the casting state of magnesium alloys with different compositions can be made by the fact that the microstructure is composed of equiaxed dendritic phase and inter-dendritic phase, and the flow rate due to ^ - 5 The solidification rate is faster, the dendrites tend to be equiaxed, and some non-circular pores between the dendrites can be found, which are the microvoids during solidification: the higher the content of the ingot (4) can be found in the 11 1270418 SEM. (d) The more interphase and eutectic's confirmed by EPMA analysis that the white phase in the eutectic is the Mg-Al phase diagram 437. (: β# produced by the eutectic reaction, the composition is MgnAl〗 2, when the content of Α1 is 28% and the content of Ζη is 4, the phase of the branch 5 becomes the β phase, and the inter-branches are separated by the eutectic α+β. There is a white a-rich phase. Therefore, the high Ζ η content makes the 28wt% A1 content a hypereutectic component, and the MgZn phase forms at the final grain boundary. The two different alloys of the zinc-bismuth alloy ingots are passed through ten times. Extrusion profiles with bright finish and no surface cracks can be obtained, showing that magnesium alloys that are difficult to be directly extruded by Prayer 10 can be converted into easily extrudable materials through multiple reciprocating extrusions and squeezed. Through the comparison of microstructures, it can be seen that the reciprocating extrusion not only destroys the casting, the structure and the defect, but instead obtains a relatively dense and recrystallized forged structure. For example, the alloy containing more than ostrich The 15 turns are thicker and more, but the reciprocating extrusion can make the β phase shatter and refine and spread evenly in the base. The average grain size can be obtained by the cross-section method: d = L/ ( ΜΝ) ” :d is the average size of the θ day particle' L is the length of the cut line, μ is the magnification Magnification, 20 Ν is the number of grain boundaries through which the cut line passes. Figure 2 shows the grain size of the @ phase and Figure 3 shows the total average grain size. It can be seen that at these two extrusion temperatures, the mouth, '3 The magnesium a gold in the grain can obtain fine crystal grains below about 丨〇, which has an effect of improving the strength elongation, superplasticity and corrosion resistance. The degree is low, and it is the lightest metal among the available structural metals. The alloy design of Invention 25 is added with an A1 content of about 10 to 28% by weight, and the effect of strengthening more of the β phase by 12 1270418 politician's but only a small increase in the density of the magnesium alloy itself, still retaining the low density of the magnesium alloy. The advantage of this is that the measured value listed in Table 2 can be found that the increase rate is not much, the highest is only 16.8%. On the other hand, the addition of 4 display Ming increases from 1G to 28%, whether it is prayer In the shape of L or the shape of the moon, the hardness is greatly improved, the casting state is increased from π s 6〇 to 180, and the extrusion type is increased from Η" 8〇 to 2〇〇, so that the extrusion hardness ratio can also be seen. The hardness of the ingot is increased by more than 20%. Table 3 shows the tensile properties of magnesium alloys with different contents of aluminum and zinc. The content of I Lu is improved, and the strength and elongation of the combination are the same as that of the die-cast magnesium alloy AZ91D. Although the elongation with the aluminum content has the opposite effect of the β phase strengthening, it still does not lose the reciprocating effect. The extrusion method can still make a complete crack-free extrusion of such alloys, so that those magnesium alloys whose aluminum content elongation tends to zero can be used at least in the state of compressive stress components and structural components. Lightweight and high strength special 15 =. The combination of the strength and elongation of this embodiment is also a waste point, that is, through the different aluminum content and heat treatment can provide a more diversified choice of application. The alloy passes through 325. (: the density after reciprocating extrusion ten times, and
13 1270418 表3常溫拉伸性質 試棒條件 降伏強度 (MPa) 抗拉強度 (MPa) 伸長率（％) Mg-lOAMZn 325°C擠型 10次 191 321 10.7 325°C擠型 後退火 155 349 25.3 350°C擠型 10次 175 368 13.7 350°C擠型 後退火 155 361 24.5 Mg-15Al-lZn 325°C擠型 10次 303 361 3.6 325°C擠型 後退火 280 352 4.0 350°C擠型 10次 305 371 1.4 350°C擠型 後退火 306 376 5.0 Mg-20Al-lZn 325°C擠型 10次 335 353 1.0 325°C擠型 後退火 307 310 1.0 350°C擠型 10次 345 370 1.1 350°C擠型 後退火 335 354 1.0 Mg-25Al-lZn 325°C擠型 10次 350 350 < 1.0 Mg-28Al-4Zn 325°C擠型 10次 360 360 < 1.0 1270418 5 10 ，為不同鋁辞含量鎂合金極化實驗的腐钮電流及腐 蝕重量損失圖。可看出都具有良好的耐蝕性，其中更發現 Mg-1:AH—Zn合金的腐#電流密度最低，腐料率也最；。 ,、、二往復式擠型後的鎂合金由於晶粒細化及均勻化，且 晶粒尺寸已達超塑性的典型晶粒尺寸上限1〇障以下，故 更表現了超塑性性質’此—特色極有利於利用超塑性的優 點來完成零組件的鍛製成型，使應用更加廣泛。圖6 ^ Mg-15AMZn 合金分別在 275、3〇〇、325及 5 X10 s條件下測試的超塑性曲線的舉例說明，可 看出優異的低溫高速超塑性特性，其最大伸長量大於 1610%，發生於325。〇及1χ1〇-νι的高應變速率。、13 1270418 Table 3 Normal temperature tensile properties Test bar conditions Drop strength (MPa) Tensile strength (MPa) Elongation (%) Mg-lOAMZn 325 ° C extrusion type 10 times 191 321 10.7 325 ° C extrusion type annealing 155 349 25.3 350°C extrusion 10 times 175 368 13.7 350°C extrusion annealing 155 361 24.5 Mg-15Al-lZn 325°C extrusion 10 times 303 361 3.6 325°C extrusion annealing 280 352 4.0 350°C extrusion 10 times 305 371 1.4 350 ° C extrusion type annealing 306 376 5.0 Mg-20Al-lZn 325 ° C extrusion type 10 times 335 353 1.0 325 ° C extrusion type annealing 307 310 1.0 350 ° C extrusion type 10 times 345 370 1.1 After 350°C extrusion type annealing 335 354 1.0 Mg-25Al-lZn 325°C extrusion type 10 times 350 350 < 1.0 Mg-28Al-4Zn 325 °C extrusion type 10 times 360 360 < 1.0 1270418 5 10 , for different A graph of the corrosion current and corrosion weight loss of the magnesium alloy polarization test. It can be seen that both have good corrosion resistance, and it is found that the corrosion resistance of Mg-1:AH-Zn alloy is the lowest, and the rate of decay is also the most; After the reciprocating extrusion of the magnesium alloy, due to grain refinement and homogenization, and the grain size has reached the upper limit of the typical grain size of superplasticity, the superplastic property is more than this. The characteristics are extremely beneficial to the use of the advantages of superplasticity to complete the forging of components, making the application more extensive. Fig. 6 ^ An example of the superplastic curve of Mg-15AMZn alloy tested under the conditions of 275, 3〇〇, 325 and 5 X10 s respectively. It can be seen that the excellent low-temperature high-speed superplastic property has a maximum elongation of more than 1610%. Occurs at 325.高 and high strain rate of 1χ1〇-νι. ,
15 20 τ 5上述可知本發明結合往復式擠型法可將以往鄭 擠型的高鋁含量鎂合金在擠型筒中鍛鍊成均質、均勻、^ 晶、細相的緻密微結構，進而能獲得輕量化、低成本、高 強度、高塑性成形能力及耐蝕的鎂合金，不但改善鎂合金 在強度方面難以突破的瓶頸，更可擴展鎂合金在3C產業、 運輸交通產業及運Μ材的制面。因此 呈 新穎性及進步性，而且可供產¥ — 十 1、座菜利用性，與發明要件相 付。，惟以上所述者，僅為本發明 Θ之只^例而已，凡依擄 本發明之各種修飾與變化，仍應包令 死匕S於本申請專利的範圍 内015 20 τ 5 It can be seen that the present invention combines the reciprocating extrusion method to train a high-aluminum magnesium alloy of the prior Zheng extruded type into a compact, uniform, homogeneous, fine-grained dense microstructure in an extrusion cylinder, thereby achieving light weight. Quantitative, low-cost, high-strength, high-plastic forming ability and corrosion-resistant magnesium alloy not only improve the bottleneck of magnesium alloy in terms of strength, but also expand the surface of magnesium alloy in 3C industry, transportation and transportation industry and transportation of coffin. Therefore, it is novel and progressive, and it can be used for the production of ¥-1, the use of the dish, and the requirements of the invention. However, the above description is only for the purpose of the present invention, and various modifications and variations of the present invention should still be made within the scope of the present patent.
上述實施例僅係為了方便說明 主張之權利範圍自應以申請專利範 於上述實施例。 而舉例而已，本發明所 圍所述為準，而非僅限 15 25The above-described embodiments are merely for the convenience of the description and the claims are intended to cover the above embodiments. By way of example, the invention is not limited to 15 25