标准编号:	GB/T 4699.8-2025
中文名称:	铬铁、硅铬合金、氮化铬铁和高氮铬铁 硅含量的测定 硅钼蓝分光光度法、氟硅酸钾滴定法和高氯酸脱水重量法
英文名称:	Ferrochromium, silicochromium, nitrogen-bearing ferrochromium and high nitrogen ferrochromium—Determination of silicon content—Silicomolybdenum blue spectrophotometric method, silicon potassium fluoride titrimetric method and perchloric acid dehydration gravimetric method
中标分类:	H11    钢铁与铁合金分析方法
行业分类:	GB    国家标准
ICS分类:	77.100 77.100    铁合金 77.100
发布机构:	国家市场监督管理总局 国家标准化管理委员会
发布日期:	2025-8-29
实施日期:	2026-3-1
标准状态:	to be valid
替代旧标准:	GB/T 5687.2-2007 铬铁、硅铬合金和氮化铬铁 硅含量的测定 高氯酸脱水重量法
翻译语言:	英文
文件格式:	PDF
中文字符数:	17000 字
翻译价格(元):	1190.0
交付时间:	付款后 1~3 个工作日

GB/T 4699.8-2025 Ferrochromium, silicochromium, nitrogen-bearing ferrochromium and high nitrogen ferrochromium—Determination of silicon content—Silicomolybdenum blue spectrophotometric method, silicon potassium fluoride titrimetric method and perchloric acid dehydration gravimetric method English, Anglais, Englisch, Inglés, えいご This is a draft translation for reference among interesting stakeholders. The finalized translation (passing thorugh draft translation, self-check, revision and varification) will be delivered upon being ordered. ICS 77.100 CCS H11 People's Republic of China National Standard GB/T 4699.8-2025 Replaces GB/T 5687.2-2007 Ferrochromium, Silicochromium, Nitrogen-bearing Ferrochromium and High Nitrogen Ferrochromium — Determination of Silicon Content — Silicomolybdenum Blue Spectrophotometric Method, Silicon Potassium Fluoride Titrimetric Method and Perchloric Acid Dehydration Gravimetric Method Issued: 2025-08-29 Implemented: 2026-03-01 Issued by: State Administration for Market Regulation Standardization Administration of China ‌Contents‌ Foreword 1 Scope 2 Normative References 3 Terms and Definitions 4 Method 1: Silicomolybdenum Blue Spectrophotometric Method 5 Method 2: Silicon Potassium Fluoride Titrimetric Method 6 Method 3: Perchloric Acid Dehydration Gravimetric Method 7 Test Report ‌Warning‌ — Users of this document should have formal laboratory working experience. This document does not address all possible safety issues. Users are responsible for taking appropriate safety and health measures and ensuring compliance with national regulations. 1 Scope This document specifies three methods for determining silicon content in ferrochromium, silicochromium, nitrogen-bearing ferrochromium and high nitrogen ferrochromium: Method 1: Silicomolybdenum blue spectrophotometric method (applicable to ferrochromium, nitrogen-bearing ferrochromium and high nitrogen ferrochromium with silicon content 0.10%-6.00% by mass) Method 2: Silicon potassium fluoride titrimetric method (applicable to silicochromium with silicon content 30.00%-50.00% by mass) Method 3: Perchloric acid dehydration gravimetric method (applicable to all specified alloys with silicon content 0.10%-60.00% by mass) 2 Normative References The following documents are indispensable for the application of this standard: GB/T 4010 Sampling and preparation of samples for chemical analysis of ferroalloys GB/T 6682 Water for analytical laboratory use — Specification and test methods GB/T 8170 Rules for rounding off numerical values and expression of limiting values GB/T 12806 Laboratory glassware — One-mark volumetric flasks GB/T 12807 Laboratory glassware — Graduated pipettes GB/T 12808 Laboratory glassware — One-mark pipettes 3 Terms and Definitions This document contains no terms requiring definition. 4 Method 1: Silicomolybdenum Blue Spectrophotometric Method 4.1 Principle The sample is dissolved in dilute hydrochloric acid and hydrogen peroxide or alkali fusion. Ammonium molybdate reacts with silicon to form silicomolybdic heteropoly acid. Oxalic acid eliminates interference from phosphorus and arsenic. The silicomolybdenum yellow is reduced to silicomolybdenum blue by ammonium ferrous sulfate, and the absorbance is measured at 680 nm wavelength using a spectrophotometer to calculate silicon content.