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機(jī)械零件所用金屬材料多種多樣，為了使生產(chǎn)、管理方便、有序，有關(guān)標(biāo)準(zhǔn)對(duì)不同金屬材料規(guī)定了它們牌號(hào)的表示方法，以示統(tǒng)一和便于采納、使用?，F(xiàn)將常用金屬材料牌號(hào)表示方法向讀者作一些簡(jiǎn)單介紹。
Mechanical parts are made of a wide variety of metal materials. In order to make production and management convenient and orderly, relevant standards for different metal materials are specified in terms of their brands, so as to show unity and easy adoption and use. We will give some brief introduction to the common methods of metal materials.
1.標(biāo)準(zhǔn)的基本概況
1. basic survey of standards
GB/T221—2000標(biāo)準(zhǔn)是參照國(guó)外鋼鐵產(chǎn)品牌號(hào)表示方法和國(guó)內(nèi)鋼鐵產(chǎn)品牌號(hào)表示方法變化（如Q345代替16Mn）等情況修訂后，于2000年4月1日發(fā)布，并于2000年11月1日開始實(shí)施。
GB/T221 2000 standard is in reference to foreign steel products designation and domestic steel products designation changes (such as Q345 instead of 16Mn) and the revised, released on April 1, 2000, and in November 1, 2000 began.

2.主要技術(shù)內(nèi)容變動(dòng)情況
2. main technical content changes
（1）由于一些鋼鐵產(chǎn)品牌號(hào)有它們專用的標(biāo)準(zhǔn)，故取消了原標(biāo)準(zhǔn)中鐵合金、鑄造合金、高溫合金、精密合金、耐蝕合金和鑄鐵、鑄鋼、粉末材料等牌號(hào)表示方法。
(1) because of some grades of steel products have their specific standards, it canceled the original standard iron alloy, cast alloy, high-temperature alloy, precision alloy, corrosion resistant alloy and cast iron, cast steel, powder material designation.
（2）一些新的鋼鐵產(chǎn)品的出現(xiàn)，更加完善了原標(biāo)準(zhǔn)。新標(biāo)準(zhǔn)增加了脫碳低磷粒鐵、含釩生鐵JP2、鑄造耐磨生鐵、保證淬透性鋼、非調(diào)質(zhì)機(jī)械結(jié)構(gòu)鋼、塑料模具鋼、取向硅鋼（電訊用）等牌號(hào)表示方法。
(2) the emergence of some new steel products has improved the original standards. The new standards include decarburization, low phosphorus iron, vanadium pig iron, JP2, cast wear-resistant pig iron, guaranteed hardenability steel, non quenched and tempered mechanical structural steel, plastic mould steel, oriented silicon steel (Telecommunications) and other brands.
（3）對(duì)不適應(yīng)科技發(fā)展和與生產(chǎn)不協(xié)調(diào)的一些用鋼牌號(hào)作了徹底改變或修改。如碳素結(jié)構(gòu)鋼A3改為Q235，低合金高強(qiáng)度結(jié)構(gòu)鋼16Mn改為Q345等。對(duì)不銹鋼、耐熱鋼和冷軋硅鋼等的牌號(hào)表示方法也做了修改。
(3) some steel grades that have not been adapted to the development of science and technology and production have been completely changed or modified. Such as carbon structural steel, A3 to Q235, low-alloy high-strength structural steel, 16Mn to Q345 and so on. The method of indication for stainless steel, heat-resisting steel and cold rolled silicon steel has also been modified.
（4）原標(biāo)準(zhǔn)中“鋼鐵產(chǎn)品牌號(hào)表示方法舉例”的，因不適用于新標(biāo)準(zhǔn)而被刪除。
(4) the example of "the method of indication of grades of iron and steel products" in the original standard is deleted because it is not applicable to the new standards.
3.鋼鐵產(chǎn)品牌號(hào)表示方法的基本原則
3. basic principles of steel product brand representation
（1）凡國(guó)家標(biāo)準(zhǔn)和行業(yè)標(biāo)準(zhǔn)中鋼鐵產(chǎn)品的牌號(hào)均應(yīng)按GB/T221-2000標(biāo)準(zhǔn)規(guī)定的牌號(hào)表示方法編寫。凡不符合規(guī)定編寫的鋼鐵產(chǎn)品牌號(hào)，應(yīng)在標(biāo)準(zhǔn)修訂時(shí)予以更改，一些新的鋼鐵產(chǎn)品，其牌號(hào)也應(yīng)按此予以編寫牌號(hào)。
(1) in every national standard and trade standard, the grades of iron and steel products shall be written in accordance with the grades indicated by the GB/T221-2000 standard. Any steel product brand that does not meet the requirements shall be changed at the time of the standard revision, and some new steel products shall be written in accordance with this brand.
（2）產(chǎn)品牌號(hào)的表示，一般采用漢語拼音字母，化學(xué)元素符號(hào)和阿拉伯?dāng)?shù)字相結(jié)合的方法來表示。
(2) the indication of the brand of the product is expressed by the combination of Chinese phonetic alphabet, chemical element symbol and Arabia numeral.
（3）采用漢語拼音字母表示產(chǎn)品名稱、用途、特性和工藝方法時(shí)，一般從代表產(chǎn)品名稱的漢語拼音中選取第一個(gè)字母。當(dāng)和另一個(gè)產(chǎn)品所選用的字母重復(fù)時(shí)，可改用第二個(gè)字母或第三個(gè)字母，或同時(shí)選取兩個(gè)漢字中的第一個(gè)拼音字母。
(3) when the Chinese phonetic alphabet is used to indicate the product name, the purpose, the characteristic and the technological method, it usually selects the first letter from the Chinese phonetic alphabet which represents the product name. When repeating the letters selected from another product, you can use second letters or third letters, or select the first phonetic letters of the two characters at the same time.
（4）暫時(shí)沒有可采用的漢字及漢語拼音的，采用符號(hào)為英文字母。
(4) there are no Chinese characters or Pinyin used for the time being, and symbols are used in English letters.
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