200407439 玫、發明說明： 【潑^明所屬泛^技領域】 發明領域 本發明係有關層狀的鋼材料，以及其製造方法。尤其 5是，本發明係有關一種較適用於諸如鑄模的層狀鋼材，以 及製造該鋼材的方法。 【先前技術】 發明背景 當一鑄造物譬如一鋁製品被以鑄造操作來生產時，熔 H)化的銘金屬會被注入一鑄模中。沉腕⑽之鋼規格)在高 溫下具有優異的強度，故一般適合作為鑄模的材料，因為 該熔化金屬會有高溫。 當於縳造操作巾時，如前所述該高溫則t金屬會接觸 該鑄模。故，熱疲乏會發生於該鑄模上。此熱疲乏會減低 15該鑄模的耐用性，並會例如在該鑄模中產生熱裂痕。且 亦會造成所謂的溶化損耗或溶解，即在鑄造操作中，有部 份的鑄模會由於其表面與鋁原料反應而耗失掉。 當發生上述狀況時，將難以製成具有預定的精確尺、 之鋁製品。即，該鋁製品的生產良率會降低。故已出$寸 20裂痕及/或溶化損耗的鑄模需要更換一新模。但若更換、*、、、 率增加，則該鋁製品的生產成本會變高，因為該模鑄 昂貴。 、：#200407439 Description of the invention: [Technical Field of Po Ming] Field of the Invention The present invention relates to a layered steel material and a method for manufacturing the same. In particular, the present invention relates to a layered steel material, such as a mold, and a method for manufacturing the steel material. [Prior Art] Background of the Invention When a casting, such as an aluminum product, is produced by a casting operation, molten metal is injected into a mold. (Steel Wrist Steel Specification) has excellent strength at high temperature, so it is generally suitable as a material for molds, because the molten metal will have high temperature. When the operation towel is made, the metal will contact the mold when the temperature is high as described above. Therefore, thermal fatigue occurs on the mold. This thermal fatigue can reduce the durability of the mold and can cause thermal cracks in the mold, for example. It also causes so-called melting loss or dissolution, that is, during the casting operation, a part of the mold is lost due to the reaction of its surface with the aluminum raw material. When the above situation occurs, it will be difficult to make an aluminum product with a predetermined precision rule. That is, the production yield of the aluminum product is reduced. Therefore, the mold that has been out of $ 20 20 cracks and / or melting loss needs to be replaced with a new mold. However, if the rate of replacement, * ,, and is increased, the production cost of the aluminum product becomes higher because the die casting is expensive. , #
為了避免熱裂痕和溶化損耗，通常會對該鑄模施C 面處理。舉例而言，氮化處理乃包括鹽 乂表 礼體法、離 5 子法；塗層處理包括物理蒸汽沈積(PVD)法或化學蒸汽沈積 (CVD)法，其中一陶瓷材料例如Tic或ΉΝ會被沈積覆設； 硫氮化處理係可形成一包含硫化鐵與氮化鐵的混合物層； 或氧化處理則能形成一含有氧化鐵的氧化物層。 但是，在上述的任一方法中，當熱疲乏阻抗增加時， 則熔化損耗阻抗會變差，而當溶化損耗阻抗改善時，熱疲 乏阻抗又會變差。例如，在該氮化處理時，一由氮化鐵所 構成的氮化物層會被形成。於此情況下，雖該溶解損耗阻 抗能改善，但其熱疲乏阻抗會變差。雖亦曾有建議容許氮 元素/參入來在鋼中形成固溶體（s〇Hd s〇ulti〇n)以提供一氮 ’、政層而不在鋼表面上提供該氮化物層。然而，在此情 兄下雖亥熱疲乏阻抗會被改善，但其溶化損耗阻抗則會 劣化。 在β亥塗層處理中，一具有1000〜3〇〇〇Vicker^l度的硬 貝陶兗覆層將會被形成。但該陶£覆層—般會具有較低的 早刃陸。故該陶瓷覆層在當該鑄模被應力所變形及/或當某些 機械衝振施於該鑄模時，將會易於剝落。又，該陶瓷覆層 與鑄杈之間的熱脹係數並不相同。因此，在鑄造操作時， 由於膨脹體積的差異故亦會發生剝離。 田由硫化鐵構成的硫化物層利用該硫氮化處理來設 在該表面上時，其溶化祕阻抗將會改善。但，當鑄造操 作重複地進彳T時，麵化物層將會㈣，目為其具有低硬 又且為多孔性的。又，該硫化物層會具有低熱疲乏阻抗， 因有氮化鐵包含於該硫化物層中。 在該氧化處理時，當作為基礎材料層的鋼因熱應力而 變形時，則所製成的氧化物層會易於剝離。 有見於上述各缺點，故曾有各種處理方法被提供來改 善該熱疲乏阻抗及溶解損耗阻抗。例如，日本早期公開專 利申清案No· 7-138733乃揭露一種處理方法，其中在離子法 的氮化處理之後，溫度會升至95〇它來施以一高頻熱處理， 俾使氮化鐵分解來減少其濃度。因分解而釋出的氮元素將 會擴散而在鋼中形成固溶體，故一氮擴散層即被製成。但 在此情況下，有些氮化鐵仍會保留而未被分解。因此，其 將不可能十分顯著地改善該熱疲乏阻抗。 在曰本早期公開專利申請案Ν〇· 56-13475,乃建議按照 離子法來在一 350〜450°C的較低溫度進行氮化處理。但 是，以處理方式所獲得之鍀模的壽命，相較於使用普通氮 化處理的鑄模’僅能延長約20至30%。以此程度的延長使 用壽命並不能可觀減少該鑄模的更換頻率，因此其不可能 充分地降低生產成本。 在曰本早期公開專利申請案Ν〇· 10-204610，乃建議以 混合物層主要包含硫化鐵及氧化鐵，另再加上氮者，來形 成於鋼的表面上。但是在此情況下，氮亦會形成氮化鐵而 存在。如前所述，該氮化鐵將會劣化其熱疲乏阻抗。 於上述技術中，將難以改善該熱疲乏阻抗，因為含有 氮化鐵的料層被製設於鋼上。 在曰本早期公開專利申請案Ν〇· 60-39155中，乃建議以 一包含FeS2的第一層及一包含？以1^的第二層來依序設在鋼 表面上。但，當此具有雙覆層的鋼被作為鑄模時，將會容 易發生剝落。因此，亦難以用此種鋼來作為鑄模。 當一藉冷卻及固化該熔融金屬來製成的鑄造物要由模 穴取出時，該鑄模亦需有潤滑性質。但是，上述之任一傳 統鑄模其潤滑性質皆有不足。故其亦難以避免所謂的，，拖 磨’’(scrffing)，而使模具可能會與鑄造物磨擦而破損。 如前所述，目前尚未有公開的技術得能全部兼顧地來 改善該等熱疲乏阻抗、溶化損耗阻抗、及推磨阻抗。 【明内^^】 發明概要 本發明的主要目的係在提供一種層狀鋼材料，其熱疲 乏阻抗與溶化損耗阻抗皆極佳，而在當該材料被用來作為 麵模日守T延長其使用寿命，且能減少鑄造物的生產成本； 及一種製造該層狀鋼材料的方法。 依據本發明之一態樣，乃在提供一種層狀鋼材，其包 含一鋼的基礎材料層，及一僅含硫化鐵和氧化鐵的混合物 層，該混合物層係為該層狀鋼材的表面。 當該層狀鋼材如前述地構成時，則可藉該氧化鐵來提 供熱疲乏阻抗及溶化損耗阻抗，而該潤滑性質則會由該硫 化鐵來提供。因此，乃可形成熱疲乏阻抗、溶化損耗阻抗、 及拖磨阻抗皆十分良好的材料，且其耐用性甚佳。 最好是，代表該硫化鐵之組成元素的^與該氧化鐵組成 元素的0之比值S/ο能滿足〇.5<S1〇<5。若該S10未大於〇 5， 則由該硫化鐵所提供的潤滑性質並不充分。相反地，若sl〇 不小於5，則該硫化鐵會易於剝落，因該氧化鐵的量較少。 最好有一氮擴散層，其中氮元素會在鋼中形成固溶 體’能設在該基材層與混合物層之間。當該氮擴散層存在 時’該基材層由於熱應力所造成的變形將會被抑止。因此， 其得以抑制該混合層的剝離。 依據本發明的另一態樣，乃在提供一種層狀的鋼材 料，其包含一鋼基材層，一氮擴散層係由鋼中之氮元素所 形成的固溶體來構成，及一僅含有氧化鐵的氧化物層，且 5亥氮擴散層係設在該基材層與氧化物層之間，而該氧化物 層係為該層狀鋼材的表面。 同樣地在此情況下，其熱疲乏阻抗與溶化損耗阻抗亦 如前述地會由該氧化鐵來提供。因此，乃能形成熱疲乏阻 抗與溶化損耗阻抗皆甚優異的材料，且其耐久性亦絕佳。 又，該基材層由熱應力所生的變形將會被抑制，因為 具有該氮擴散層。因此，其乃得以抑制該氧化物層的剝離。 在任何各例中，最好該氧化鐵係為以3〇4。因為相較於 Fee;及FeO,該FqO4對改善溶化損耗阻抗會更為優異。 由上述之層狀鋼材所製成之一較佳物品係為供用於鑄 造插作的每模。 依據本發明之又另一態樣，乃在提供一種層狀鋼狀的 製造方法，該鋼材包含一鋼的基材層，及一混合層僅由碚 化鐵與氧化鐵所構成，該混合層係為該層狀鋼材的表面； 而該方法包含·· 藉同時硫化及氧化該鋼而來製成該混合層。 當該鋼被同時地來硫化及氧化時，將能容易地製成該 浪合層’而使賴純_熱疲核抗、溶化損耗阻抗、 及潤滑性質。X ’如此獲得的混合層係使用該基材層來製 成者。該混合層並非-疊覆或層合在基材層上的覆層膜。 故，該混合層幾乎不會由該基材層剝離。 該混合層幾乎不會剝離的層狀鋼材，亦可在製成該混 合層之耵，在鋼中形成氮元素的固溶體作為氮擴散層而來 獲得。 依據本發明之又另一態樣，乃在提供一種層狀鋼材的 製造方法，該鋼材包含一鋼構成的基材層，一氮擴散層係 由鋼中的氮元素形成之固溶體所構成，及一僅由氧化鐵構 成的氧化物層，且該氮擴散層係設在基材層與氧化物層之 間，该氧化物層則為該層狀鋼材的表面；而該方法包含： 在該鋼中製成氮元素的固溶體來作為氮擴散層；及氧 化設有該氮擴散層的鋼來製成該氧化物層。 於上述兩種製造方法中，最好氧係被用來作為氧化該 鋼的氧化劑，且該氧會以部份壓力來供應，而使Fe3o4能被 獲得作為該氧化鐵。即，該壓力會使其容易地製成。 該Fe3〇4能優異地改善溶化損耗阻抗。 本發明之上述及其它的目的、特徵和優點等，將可由 以下說明配合所附圖式而更清楚瞭解，在圖式中乃示出本 發明之一較佳實施例來作說明範例。 圖式簡單說明 弟1圖為一垂向剖視圖示出设有本發明一實施例之禱 模的鑄造裝置之主要構件； 第2圖為一放大圖示出第1圖中之铸造裝置的固定模之 模穴表面的主要部份；及 第3圖為一放大圖示出另一實施例之鑄模（固定模）的模 穴表面之主要部份。 C實施方式】 較佳實施例之詳細說明 本發明之層狀鋼材及其製造方法將參照所附圖式來詳 細說明如下，而以有關由該層狀鋼材製成的鑄模之較佳實 施例來舉例說明。 第1圖不出一鑄造裝置之主要構件的垂直截面圖，其中 設有本發明一實施例的鑄模。該鑄造裝置1〇可用來铸造一 未示出的筒狀塊體，例如鱗造物。該鑄造裝置1〇包 含模具等，即一固定模12，側可動模14、16，及一上可動 模18。尤其是，該固定模12設有一孔銷2〇。有一套筒^會 於外部套裝在該⑽20上’並有―可獲得該筒狀塊體的模 穴24形成於該鑄造裝置1〇中。 一砂心26會被置設在該模穴24击 甲’而形成該筒狀塊體 的水套。該砂心、26係被-未示出的切物所撐持。 該各固定模12、側可動模14、j < 16、及上可動模18等皆 由鋼所構成，其具有SKD61的基枒 1層。在該各模具12、14、 16、18等之模穴24的表面（以下簡瀚, k穴表面”)上，會藉處 理該SKD61基材的表面來製成二料展 詳言之，如第2圖所示，該固宏 心輪12的模穴表面具有一 200407439 三層結構，包括該基材層30係由SKD61所構成，一氮擴散 層32 ’及一混合層34。於本實施例中，該氮擴散層32和混 合層34皆為使用該基材層3〇來製成的料層。該氮擴散層32 與此合層34皆非堆疊式層合在該基材層3〇上的覆設膜。 5 該氮擴散層32係被製成使氮元素擴散於SKD61中來形 成固溶體。該固溶體的氮元素會鍵結於該SKD61(鋼）的構成 元素Fe及C，而形成三元素固溶體。此固溶體於後簡稱 為”Fe(C，N)’’。 該氮擴散層32會抑制該SKD61(即基材層30)因熱應力 10所造成的變形。因此，可防止該混合層34由該氮擴散層32 剝離。換言之，當該氮擴散層32存在時，該混合層34幾乎 不會剝離。 該氮擴散層32的厚度例如可為50至250// m。 該混合層34係僅由同時硫化及氧化該SKD61所形成的 15硫化鐵和氧化鐵來組成之一料層。即是，沒有任何氮化鐵 包含於该混合層3 2中。 該硫化鐵係為可提供潤滑性質給該鑄模的成分。由於 该硫化鐵的存在，故該鑄模的潤滑性質會顯著地改善。因 此，其乃可抑止拖磨的發生。該硫化鐵係散佈在氧化鐵中。 〇換a之，該硫化鐵會被氧化鐵固定於該鑄模的表面上。 該混合層34的厚度最好能在〇·5至20#m的範圍内。若 /、厚度小於0.5 am，則提供熱疲乏阻抗、溶化損耗阻抗、 及/閏滑性質的效果會較不足。相反地，若其厚度大於20// m ’則該混合層34會易於由該氮擴散層32剝離。 12 虱化鐵之熱疲乏阻抗及溶化損耗阻抗皆十分優異。當 該氧化鐵存在於表面上時，將得能改善該鑄模的熱疲乏阻 抗及溶化損耗阻抗。 最好該硫化鐵之構成元素s和氧化鐵的構成元素0之 間的比值係滿足以下公式G): 〇.5<S/0<5 ⑴ 若S/ο不大於0.5，則得自該硫化鐵的潤滑效果並不充 分。相反地，若s/o不小於5，則該硫化鐵會易於剝離，因 為該氧化鐵的分量減少。 該氧化鐵最好為四氧化三鐵(ρ^04)。在此情況下，其 相較於該氧化鐵為Fe2〇3或FeO的狀況，將更能改善溶化損 耗阻抗。 如上述的氮擴散層32與混合層34亦會形成於該等側可 動模14、16及上可動模18之其它模穴表面中。 在模穴表面具有氮擴散層32與混合層34的固定模12可 如下述方法來製成。首先，一具有該固定模12之形狀的預 製物，會被先以習知的製法來由一作為胚材原料的SKD61 製成。 然後，該氮擴散層32會在一形成氮固溶體的步驟中， 被製成於該預製物的模穴表面中。詳言之，該預製物會被 置於一處理室中，且該處理室的溫度會保持在45〇〜58〇χ： °C。然後，氨氣和氫氣會被供入該處理室内。由該氨氣熱 分解所釋出的氮元素會擴散於該預製物中，嗣該氮元素會 鍵結於該SKD61的構成元素Fe及c。因此，該固溶體Fe(c、 200407439 % N)會被製成於該預製物的表面中。結果，其中之氮元素形 成該固溶體的氮擴散層32,即會被製設在由鋼構成的基材 層30上。 氫氣係為用來控制氨氣之活性的成分。藉著與氨氣一 5 起來供入一預定量的氫氣，則製成該固溶體之前，將能抑 制氮化鐵的生成。 在停止供應該氨氣與氫氣之後，溫度會保持在500〜 550°C，而氮氣、氧氣、及硫化氫氣體將會被供入來進行一 混合物的形成步驟。於此步驟中，氧氣的部份壓力會被控 10 制為能製成四氧化三鐵(Fe304)。該氧氣的部份壓力最好係 為 1·013χΗΓ2。至 1.013xl0_1°Pa。 該SKD61之構成元素的Fe，將會與供入氣體中所含的 氧氣和硫化氫氣體來反應。因此，即會製成該混合層34， 其係由四氧化三鐵(Fe304)與硫化鐵(FeS)所組成。 15 在此過程中，Fe(C、N)會擴散於該基材層30的更深部 份内。因此，Fe(C、N)不會保留在該混合層34中。於該混 合層34的製造過程中，氮元素源例如氨氣和氮氣並不會被 供入。因此，該混合層34内不會含有氮化鐵。 故，該固定模12在模穴表面中會具有該氮擴散層32及 20 混合層34。當然，一類似的表面處理亦會施加於要被製成 該側可動模14、16及上可動模18之各預製物的模穴^表面。 故，該等側可動模14、16與上可動模18將會被製成最終成 品。 如上所述，依據本發明之該實施例，該等模具12、14、 14 200407439 16、18將可被容易製成，其中該預製物係被置於處理室中， 且預定的氣體會被供入該腔室内。該各模具12、14、16、 18皆會具有氮擴散層32和混合層34。 該筒狀塊體係使用以前述方法構製的鑄模12、14、16、 5 18等來如下地製成。In order to avoid thermal cracking and melting loss, the C-face treatment is usually applied to the mold. For example, the nitriding process includes the salt method and the ionization method; the coating process includes the physical vapor deposition (PVD) method or the chemical vapor deposition (CVD) method. It is deposited and overlaid; the sulfur nitriding treatment system can form a mixed layer containing iron sulfide and iron nitride; or the oxidation treatment can form an oxide layer containing iron oxide. However, in any of the above methods, when the thermal fatigue resistance is increased, the melting loss resistance is deteriorated, and when the melting loss impedance is improved, the thermal fatigue resistance is deteriorated again. For example, during the nitriding treatment, a nitride layer composed of iron nitride is formed. In this case, although the dissolution loss impedance can be improved, its thermal fatigue resistance will be deteriorated. It has also been suggested to allow nitrogen / incorporation to form a solid solution (sohd soultion) in the steel to provide a nitrogen 'layer instead of the nitride layer on the surface of the steel. However, in this case, although the thermal fatigue resistance will be improved, the melting loss resistance will be deteriorated. In the beta-hai coating process, a hard shell coating with a degree of 1000 to 3000 Vicker ^ l will be formed. However, the ceramic cladding will generally have a lower early edge. Therefore, the ceramic coating will be easily peeled off when the mold is deformed by stress and / or when some mechanical shock is applied to the mold. In addition, the coefficient of thermal expansion between the ceramic coating and the casting branch is different. Therefore, during the casting operation, peeling also occurs due to the difference in expansion volume. When a sulfide layer made of iron sulfide is provided on the surface by using the sulfur nitriding treatment, its melting resistance will be improved. However, when the casting operation is repeatedly performed, T, the surface layer will be deflated to be low in hardness and porous. In addition, the sulfide layer may have a low thermal fatigue resistance because iron nitride is contained in the sulfide layer. In this oxidation treatment, when the steel serving as the base material layer is deformed by thermal stress, the produced oxide layer is easily peeled. In view of the above disadvantages, various treatment methods have been provided to improve the thermal fatigue resistance and the dissipative loss resistance. For example, Japanese Early Laid-open Patent Application No. 7-138733 discloses a treatment method in which after the nitridation treatment by the ion method, the temperature will rise to 95 ° C to apply a high-frequency heat treatment to the iron nitride Decompose to reduce its concentration. The nitrogen element released by the decomposition will diffuse and form a solid solution in the steel, so a nitrogen diffusion layer is made. However, in this case, some iron nitrides will remain without being decomposed. Therefore, it will not be possible to significantly improve this thermal fatigue resistance. In the earlier published patent application No. 56-13475, it was suggested to perform nitriding at a lower temperature of 350 ~ 450 ° C according to the ion method. However, the life of the mold obtained by the treatment method can only be extended by about 20 to 30% compared to the mold 'using the ordinary nitriding treatment. Prolonging the service life to this extent does not significantly reduce the frequency of changing the mold, so it is impossible to sufficiently reduce the production cost. In the earlier published patent application No. 10-204610, it was suggested that the mixture layer mainly contains iron sulfide and iron oxide, plus nitrogen to form on the surface of the steel. However, in this case, nitrogen also exists as iron nitride. As mentioned earlier, this iron nitride will degrade its thermal fatigue resistance. In the above technique, it will be difficult to improve the thermal fatigue resistance because a layer containing iron nitride is made on steel. In this earlier published patent application No. 60-39155, it was suggested that a first layer containing FeS2 and a containing? The second layer of 1 ^ is arranged on the steel surface in order. However, when this double-clad steel is used as a mold, it will be easily peeled. Therefore, it is also difficult to use such steel as a mold. When a casting made by cooling and solidifying the molten metal is to be taken out of the cavity, the mold also needs to be lubricating. However, any of the above-mentioned conventional molds has insufficient lubrication properties. Therefore, it is also difficult to avoid the so-called "scrffing", and the mold may be rubbed with the cast and damaged. As mentioned earlier, there are currently no publicly available technologies that are able to improve the thermal fatigue resistance, the melting loss resistance, and the grinding resistance in a balanced manner. [Akichi ^^] Summary of the invention The main purpose of the present invention is to provide a layered steel material with excellent thermal fatigue resistance and melting loss resistance, and when the material is used as a surface mold, the day guard T extends its And a method for manufacturing the layered steel material. According to one aspect of the present invention, a layered steel material is provided, which comprises a steel base material layer and a mixture layer containing only iron sulfide and iron oxide, and the mixture layer is the surface of the layered steel material. When the layered steel is constructed as described above, the iron oxide can be used to provide the heat fatigue resistance and the melting loss resistance, and the lubricating property is provided by the iron sulfide. Therefore, it can form a material with very good thermal fatigue resistance, melting loss resistance, and drag resistance, and its durability is very good. Preferably, a ratio S / o of ^ representing the constituent element of the iron sulfide and 0 of the constituent element of the iron oxide satisfies 0.5 < S1〇 < 5. If the S10 is not more than 0.05, the lubricating properties provided by the iron sulfide are insufficient. On the contrary, if sl0 is not less than 5, the iron sulfide may be easily peeled because the amount of the iron oxide is small. It is preferable to have a nitrogen diffusion layer, in which a nitrogen element forms a solid solution in the steel, and can be disposed between the base material layer and the mixture layer. When the nitrogen diffusion layer is present, the deformation of the substrate layer due to thermal stress will be suppressed. Therefore, it is possible to suppress peeling of the mixed layer. According to another aspect of the present invention, a layered steel material is provided, which includes a steel substrate layer, a nitrogen diffusion layer composed of a solid solution formed by nitrogen elements in the steel, and An oxide layer containing iron oxide, and a nitrogen diffusion layer is provided between the substrate layer and the oxide layer, and the oxide layer is the surface of the layered steel material. In this case as well, the thermal fatigue resistance and the melting loss resistance will be provided by the iron oxide as before. Therefore, it can form a material with excellent thermal fatigue resistance and melting loss resistance, and its durability is also excellent. In addition, the substrate layer is prevented from being deformed by thermal stress because it has the nitrogen diffusion layer. Therefore, it is possible to suppress peeling of the oxide layer. In any case, it is preferable that the iron oxide is 304. Because compared with Fee; and FeO, the FqO4 is more excellent for improving the melting loss resistance. One of the preferred articles made from the above-mentioned layered steel is each mold for casting inserts. According to another aspect of the present invention, a layered steel-like manufacturing method is provided. The steel material includes a steel substrate layer, and a mixed layer is only composed of tritiated iron and iron oxide. The mixed layer Is the surface of the layered steel; and the method includes making the mixed layer by simultaneously vulcanizing and oxidizing the steel. When the steel is simultaneously vulcanized and oxidized, it will be easy to make the wave-coated layer ' to make Lai Chun_heat fatigue resistance, melting loss resistance, and lubricating properties. The X 'thus obtained mixed layer was produced using this base material layer. The mixed layer is not a cover film laminated or laminated on the substrate layer. Therefore, the mixed layer is hardly peeled from the base material layer. The layered steel material where the mixed layer is hardly peeled off can also be obtained by forming a solid solution of nitrogen element in the steel as a nitrogen diffusion layer after forming the mixed layer. According to another aspect of the present invention, a method for manufacturing a layered steel material is provided. The steel material includes a base material layer made of steel, and a nitrogen diffusion layer is composed of a solid solution of nitrogen in the steel. And an oxide layer composed only of iron oxide, and the nitrogen diffusion layer is provided between the substrate layer and the oxide layer, and the oxide layer is the surface of the layered steel; and the method includes: A solid solution of nitrogen is made in the steel as a nitrogen diffusion layer; and the steel provided with the nitrogen diffusion layer is oxidized to make the oxide layer. In the above two manufacturing methods, it is preferable that an oxygen system is used as an oxidizing agent for oxidizing the steel, and the oxygen is supplied at a partial pressure, so that Fe3o4 can be obtained as the iron oxide. That is, this pressure makes it easy to make. This Fe304 can excellently improve the melting loss resistance. The above and other objects, features, and advantages of the present invention will be more clearly understood from the following description in conjunction with the accompanying drawings. In the drawings, a preferred embodiment of the present invention is shown as an illustrative example. Brief description of the drawings: Figure 1 is a vertical sectional view showing the main components of a casting device provided with a prayer mold according to an embodiment of the present invention; Figure 2 is an enlarged view showing a fixed mold of the casting device in Figure 1 The main part of the cavity surface of the cavity; and FIG. 3 is an enlarged view showing the main part of the cavity surface of the mold (fixed mold) of another embodiment. Embodiment C] Detailed description of the preferred embodiment The layered steel material and manufacturing method of the present invention will be described in detail with reference to the attached drawings, and a preferred embodiment of a casting mold made of the layered steel material for example. Fig. 1 does not show a vertical sectional view of the main components of a casting device, in which a mold according to an embodiment of the present invention is provided. The casting device 10 can be used to cast a cylindrical block, not shown, such as a scale. The casting device 10 includes a mold or the like, that is, a fixed mold 12, side movable molds 14, 16 and an upper movable mold 18. In particular, the fixed mold 12 is provided with a hole pin 20. A sleeve ^ will be fitted on the ⑽20 'on the outside and a cavity 24 for obtaining the cylindrical block is formed in the casting device 10. A sand core 26 will be placed in the cavity 24 to strike a nail 'to form a water jacket of the cylindrical block. The sand core 26 is supported by a cut-out not shown. Each of the fixed mold 12, the side movable mold 14, j < 16, and the upper movable mold 18 are made of steel, and have a base SKD61 of one layer. On the surface of the cavity 24 of the molds 12, 14, 16, 18, etc. (hereinafter referred to as the “K-hole surface”), the surface of the SKD61 substrate is processed to make a second material exhibition. As shown in FIG. 2, the cavity surface of the Guhong core wheel 12 has a 200304439 three-layer structure, including the base material layer 30 made of SKD61, a nitrogen diffusion layer 32 ′, and a mixed layer 34. In this implementation, In the example, the nitrogen diffusion layer 32 and the mixed layer 34 are both layers made of the substrate layer 30. The nitrogen diffusion layer 32 and the composite layer 34 are non-stacked and laminated on the substrate layer 3 Overlay film on 〇. 5 The nitrogen diffusion layer 32 is made by diffusing nitrogen into SKD61 to form a solid solution. The nitrogen in the solid solution is bonded to Fe, a constituent element of SKD61 (steel). And C to form a three-element solid solution. This solid solution is hereinafter referred to as "Fe (C, N)". The nitrogen diffusion layer 32 suppresses deformation of the SKD 61 (i.e., the substrate layer 30) due to thermal stress 10. Therefore, the mixed layer 34 can be prevented from being peeled from the nitrogen diffusion layer 32. In other words, when the nitrogen diffusion layer 32 is present, the mixed layer 34 is hardly peeled. The thickness of the nitrogen diffusion layer 32 may be, for example, 50 to 250 // m. The mixed layer 34 is only a material layer composed of 15 iron sulfide and iron oxide formed by simultaneously sulfiding and oxidizing the SKD 61. That is, no iron nitride is contained in the mixed layer 32. The iron sulfide is a component that can provide lubricating properties to the mold. Due to the presence of the iron sulfide, the lubricating properties of the mold are significantly improved. Therefore, it can prevent the occurrence of drag. The iron sulfide is dispersed in iron oxide. 〇 In other words, the iron sulfide will be fixed on the surface of the mold by iron oxide. The thickness of the mixed layer 34 is preferably in a range of 0.5 to 20 #m. If the thickness is less than 0.5 am, the effects of providing thermal fatigue resistance, melting loss resistance, and / or slippage properties are insufficient. Conversely, if the thickness is greater than 20 // m ', the mixed layer 34 is easily peeled from the nitrogen diffusion layer 32. 12 The thermal fatigue resistance and melting loss resistance of iron lice are excellent. When the iron oxide is present on the surface, the thermal fatigue resistance and the melting loss resistance of the mold will be improved. Preferably, the ratio between the constituent element s of the iron sulfide and the constituent element 0 of the iron oxide satisfies the following formula G): 0.5 < S / 0 < 5 ⑴ If S / ο is not greater than 0.5, it is obtained from the sulfurization The lubrication effect of iron is not sufficient. On the contrary, if s / o is not less than 5, the iron sulfide is easily peeled because the amount of the iron oxide is reduced. The iron oxide is preferably triiron tetroxide (ρ ^ 04). In this case, the melting loss resistance will be improved more than when the iron oxide is Fe203 or FeO. As described above, the nitrogen diffusion layer 32 and the mixed layer 34 are also formed in the surfaces of the movable molds 14 and 16 on the side and the other cavity surfaces of the upper movable mold 18. The stationary mold 12 having the nitrogen diffusion layer 32 and the mixed layer 34 on the surface of the cavity can be manufactured as follows. First, a preform having the shape of the fixed mold 12 is first made of SKD61 as a raw material by a conventional manufacturing method. Then, the nitrogen diffusion layer 32 is formed on the surface of the cavity of the preform in a step of forming a nitrogen solid solution. In detail, the preform is placed in a processing chamber, and the temperature of the processing chamber is maintained at 45 ° to 58 ° C: ° C. Ammonia and hydrogen are then fed into the process chamber. The nitrogen element released by the thermal decomposition of the ammonia gas will diffuse into the preform, and the nitrogen element will be bonded to the constituent elements Fe and c of the SKD61. Therefore, the solid solution Fe (c, 200407439% N) is made in the surface of the preform. As a result, the nitrogen diffusion layer 32 in which the nitrogen element forms the solid solution is formed on the base material layer 30 made of steel. Hydrogen is a component used to control the activity of ammonia. By supplying a predetermined amount of hydrogen together with the ammonia gas, the formation of iron nitride can be suppressed before the solid solution is made. After the supply of ammonia and hydrogen is stopped, the temperature will be maintained at 500 ~ 550 ° C, and nitrogen, oxygen, and hydrogen sulfide gas will be supplied to perform a mixture formation step. In this step, part of the pressure of oxygen will be controlled to be able to make ferric iron oxide (Fe304). The partial pressure of this oxygen is preferably 1.013xΗΓ2. To 1.013xl0_1 ° Pa. Fe, which is a constituent element of SKD61, reacts with oxygen and hydrogen sulfide gas contained in the supplied gas. Therefore, the mixed layer 34 is formed, which is composed of ferric tetroxide (Fe304) and iron sulfide (FeS). 15 During this process, Fe (C, N) will diffuse into deeper portions of the substrate layer 30. Therefore, Fe (C, N) does not remain in the mixed layer 34. During the manufacturing process of the mixed layer 34, a nitrogen element source such as ammonia gas and nitrogen gas is not supplied. Therefore, iron nitride is not contained in the mixed layer 34. Therefore, the fixed mold 12 will have the nitrogen diffusion layer 32 and the mixed layer 34 in the cavity surface. Of course, a similar surface treatment is also applied to the cavity surface of each preform to be made into the side movable molds 14, 16 and the upper movable mold 18. Therefore, the side movable molds 14, 16 and the upper movable mold 18 will be made into a final product. As described above, according to the embodiment of the present invention, the molds 12, 14, 14 200407439 16, 18 will be easily made, wherein the preform is placed in a processing chamber, and a predetermined gas is supplied. Into the chamber. Each of the molds 12, 14, 16, 18 will have a nitrogen diffusion layer 32 and a mixed layer 34. This cylindrical block system is manufactured as follows using the molds 12, 14, 16, 5, 18, etc. which were constructed by the aforementioned method.
首先，該模穴24會經由一未示出的澆道和閘口來填滿 溶融金屬例如鋁，其中該固定模12，側可動模14、16、及 上可動模18等會如第1圖所示地夹合。在模具内的熔融金屬 每在大約85〜lOOMPa的南壓力下來被鑄造。 1〇 於此過程中，該鋼基材層30由於熱應力造成的變形將 會被抑止，因為在各模具12、14、16、18等之模穴表面中 设有該氮擴散層32。故而，其乃可抑制該混合層34的剝離。First, the mold cavity 24 will be filled with molten metal such as aluminum through a gate and a gate not shown. The fixed mold 12, the side movable molds 14, 16 and the upper movable mold 18 will be filled as shown in FIG. Show ground clamp. Each molten metal in the mold is cast at a south pressure of about 85 to 100 MPa. 10 During this process, the deformation of the steel base material layer 30 due to thermal stress will be suppressed because the nitrogen diffusion layer 32 is provided in the cavity surface of each of the molds 12, 14, 16, 18, and the like. Therefore, it is possible to suppress peeling of the mixed layer 34.
该混合層34係設在各模具12、14、16、18的模穴表面 中，而包含氧化物能改善該熱疲乏阻抗和溶化損耗阻抗。 15且，因沒有氮化鐵包含於該混合層34中，故各模具12、14、 16、18的熱疲乏阻抗將會顯著改善。因此，在各模具12、 14、16、18中的裂縫等能被顯著地抑制。且各模具12、14、 16、18和鋁的反應亦會被抑止，因為該溶化損耗阻抗己改 善。 2〇 在高壓下來鑄造的鋁熔融金屬當冷卻時即會固化。於 固化元成之後’當該等模具打開時，上可動模18和側可動 模Η、16將會與該固定模12分開。然後，成為鑄造產生的 同狀塊體會被以一未示出的頂出銷來取出。 在該筒狀塊體與模穴表面之間的磨擦阻力很小，因有 15 200407439 硫化鐵包含於該混合層34中。故任何拖磨亦可被抑止。 在本發明的實施例中，該混合層34係被設在氣擴散層 32上。或者，該混合層34亦可直接設在鋼的表面中。於此 情況下，製成該混合層的步驟將可直接進行，而不必有如 5 前述之製成氮固溶體的步驟。 又或者，該混合層34亦可如同被設在各模具12、14、 16、18等之模穴表面中地來設在整體表面中。同樣地在此 情況下’該氮擴散層32亦可被製設。 在另一實施例中，該固定模12亦可被製成如第3圖所 10 示。在第3圖及以下說明中，相同於第1、2圖的構成元件係 以相同編號來標示，且其說明不再冗述。 於本例中，該固定模12的模穴表面具有三層結構，包 含一 SKD61的基材層3〇，一氮擴散層32，一氧化物層4〇。 5亥氧化物層40係為一僅由SKD61氧化所得的氧化鐵來 15 構成的料層。即，沒有氮化鐵包含於該氧化物層40中。 該氧化物層40的厚度最好係在0.5至20//m的範圍内。 若其厚度小於0.5//m，則提供熱疲乏阻抗及溶解損耗阻抗 的效用會不足。相反地，若其厚度大於2〇#m，則該氧化物 層40會易於由該氮擴散層32剝離。 20 该氧化鐵的熱疲乏阻抗和溶化損耗阻抗皆甚優異。 即，當該氧化鐵存在於該表面上時，其將能改善該鑄模的 熱疲乏阻抗及溶化損耗阻抗。 最好該氧化鐵係為四氧化三鐵(Fe3〇4)。在此情況下， 其相#父於该氧化鐵為Fe2〇3和FeO的情況，會更能改善該溶 16 200407439 化損耗阻抗。 如上所述之氮擴散層32與氧化物層40亦會分別設在側 可動模14、16及上可動模18的模穴表面上。 模穴表面中具有氮擴散層32和氧化物層4〇的固定模12 5即可依據上述的程序來製得。首先，會以如同前述的方法 來進行操作，而在該固定模12之預製物的模六表面中形成 氮擴散層3 2。 在中止氨氣及氫氣的供應而完成該氮擴散層32的製造 之後，溫度會保持在500〜55(TC，然後氫氣和氧氣會被供 10入來進行製造氣化物層的步驟。在此過程中，氧氣的部份 壓力會被控制而來生成Fe3〇4。該氧氣的部份壓力最好係為 1·03χ1(Τ20至 i.〇i3xl(T10pa。The mixed layer 34 is provided on the cavity surface of each of the molds 12, 14, 16, 18, and the inclusion of an oxide can improve the thermal fatigue resistance and the melting loss resistance. 15. Furthermore, since no iron nitride is contained in the mixed layer 34, the thermal fatigue resistance of each of the molds 12, 14, 16, 18 will be significantly improved. Therefore, cracks and the like in each of the molds 12, 14, 16, 18 can be significantly suppressed. In addition, the reactions between the molds 12, 14, 16, 18 and aluminum will be suppressed because the melting loss resistance has been improved. 20 Aluminum molten metal cast under high pressure solidifies when cooled. After the curing element is formed ', when the molds are opened, the upper movable mold 18 and the side movable molds Η, 16 will be separated from the fixed mold 12. Then, the homogeneous block produced by casting is taken out with an eject pin not shown. The frictional resistance between the cylindrical block and the surface of the cavity is small because 15 200407439 iron sulfide is contained in the mixed layer 34. Therefore, any drag can be suppressed. In the embodiment of the present invention, the mixed layer 34 is provided on the gas diffusion layer 32. Alternatively, the mixed layer 34 may be directly provided on the surface of the steel. In this case, the step of forming the mixed layer can be performed directly without the step of forming a nitrogen solid solution as described in 5 above. Alternatively, the mixed layer 34 may be provided in the entire surface as if it were provided in the cavity surface of each of the molds 12, 14, 16, 18, and the like. Similarly, in this case, the nitrogen diffusion layer 32 may be formed. In another embodiment, the fixed mold 12 can also be made as shown in FIG. 3. In Fig. 3 and the following description, the same components as those in Figs. 1 and 2 are denoted by the same numbers, and descriptions thereof will not be repeated. In this example, the cavity surface of the fixed mold 12 has a three-layer structure, including a base layer 30 of SKD61, a nitrogen diffusion layer 32, and an oxide layer 40. The oxidized oxide layer 40 is a material layer composed only of iron oxide 15 obtained by the oxidation of SKD61. That is, no iron nitride is contained in the oxide layer 40. The thickness of the oxide layer 40 is preferably in a range of 0.5 to 20 // m. If its thickness is less than 0.5 // m, the utility of providing thermal fatigue resistance and dissolution loss resistance will be insufficient. Conversely, if the thickness is greater than 20 #m, the oxide layer 40 may be easily peeled from the nitrogen diffusion layer 32. 20 The iron oxide has excellent thermal fatigue resistance and melting loss resistance. That is, when the iron oxide is present on the surface, it will improve the thermal fatigue resistance and the melting loss resistance of the mold. Preferably, the iron oxide system is triiron tetroxide (Fe304). In this case, the phase loss is better than the case where the iron oxide is Fe203 and FeO. As described above, the nitrogen diffusion layer 32 and the oxide layer 40 are also provided on the cavity surfaces of the side movable molds 14, 16 and the upper movable mold 18, respectively. The fixed mold 125 having the nitrogen diffusion layer 32 and the oxide layer 40 on the surface of the cavity can be prepared according to the above procedure. First, a nitrogen diffusion layer 32 is formed on the surface of the mold 6 of the preform of the fixed mold 12 in the same manner as described above. After the supply of ammonia and hydrogen is stopped and the production of the nitrogen diffusion layer 32 is completed, the temperature will be maintained at 500 ~ 55 ° C, and then hydrogen and oxygen will be supplied to 10 to perform the step of manufacturing the vaporized layer. In the process, part of the pressure of oxygen will be controlled to produce Fe304. The partial pressure of this oxygen is preferably 1.03x1 (T20 to i.〇i3xl (T10pa.
Fe係為該SKD61的構成元素之一，其將會與供入的氧 氣反應。因此，由Fe3〇4構成的氧化物層即可被製成。 15 於此過程中，Fe(C、N)會擴散至該基材層30的較深部 份。因此，：Fe(C、N)不會保留在該氧化物層4〇中。在製造 该氧化物層40的過程中，氮元素源例如氨氣及氮氣並不會 被供入。所以，沒有任何氮化鐵會包含於該氧化物層4〇中。 故，該固定模12在模穴表面中會具有該氮擴散層32及 2〇氧化物層40。當然，一類同的表面處理亦會施加於要被製 成側可動模I4、16及上可動模18之預製物的模六表面。故， 該等模具14、16、18乃可製成最終成品。 該筒狀塊體亦係使用具有上述各模具丨2、14、16、18 的鑄造裝置，以如前所述之相同方式來鑄造製成。 17 200407439 以上各實施例係使用一鑄模作為該層狀鋼材之範例來 說明。但本發明並不受限於該等實施例而有各種不同的用 途。 如上所述，其乃可藉在表面層中製設氧化物層或含有 5 氧化鐵與硫化鐵的混合層，而來獲得熱疲乏阻抗、溶化損 耗阻抗及拖磨阻抗皆極優異的材料。 【圖式簡單說明3 第1圖為一垂向剖視圖示出設有本發明一實施例之鑄 模的鑄造裝置之主要構件； 10 第2圖為一放大圖示出第1圖中之鑄造裝置的固定模之 模穴表面的主要部份；及 第3圖為一放大圖示出另一實施例之鑄模（固定模）的模 穴表面之主要部份。 【圖式之主要元件代表符號表】 10…鑄造裝置 24…模穴 12...固定模 26…砂心 14，16…側可動模 30…基材層 18…上可動模 32…氮擴散層 20…孔鎖 34···混合層 22…套筒 40···氧化物層Fe is one of the constituent elements of this SKD61, and it will react with the supplied oxygen gas. Therefore, an oxide layer made of Fe304 can be made. 15 In this process, Fe (C, N) will diffuse to a deeper portion of the substrate layer 30. Therefore, Fe (C, N) does not remain in the oxide layer 40. During the production of the oxide layer 40, a source of nitrogen elements such as ammonia and nitrogen is not supplied. Therefore, no iron nitride is contained in the oxide layer 40. Therefore, the fixed mold 12 will have the nitrogen diffusion layer 32 and the 20 oxide layer 40 on the surface of the cavity. Of course, a similar type of surface treatment will also be applied to the mold six surfaces of the preforms to be made into the side movable molds I4, 16 and the upper movable mold 18. Therefore, these molds 14, 16, 18 can be made into final products. The cylindrical block is also cast and manufactured in the same manner as described above using a casting device having the above-mentioned molds 2, 14, 16, 18. 17 200407439 The above embodiments have been described using a mold as an example of the layered steel. However, the present invention is not limited to these embodiments but has various uses. As mentioned above, it is possible to obtain a material with excellent thermal fatigue resistance, melting loss resistance, and drag resistance by forming an oxide layer or a mixed layer containing iron oxide and iron sulfide in the surface layer. [Brief Description of the Drawings 3] FIG. 1 is a vertical sectional view showing the main components of a casting device provided with a mold of an embodiment of the present invention; 10 FIG. 2 is an enlarged view showing the casting device of FIG. The main part of the cavity surface of the fixed mold; and FIG. 3 is an enlarged view showing the main part of the cavity surface of the mold (fixed mold) of another embodiment. [Representative symbols for main elements of the drawing] 10 ... casting device 24 ... mold cavity 12 ... fixed mold 26 ... sand core 14,16 ... side movable mold 30 ... substrate layer 18 ... upper movable mold 32 ... nitrogen diffusion layer 20 ... hole lock 34 ... mixed layer 22 ... sleeve 40 ... oxide layer