91视频专区

无翼乌火影之修罗道冲最新无翼乌火影之修罗道推荐-蚕蚕阅读

思域以其动感的设计、优秀的操控性和经济的燃油消耗受到好评。新款思域在保持驾驶乐趣的同时,也优化了乘坐舒适性和安全性,适合追求驾驶体验的家庭。

2024年12月15日,当儿媳或女婿不尊重您时,首先要学会的便是“不理”,将其当成外人。这里的“外人”并非是要刻意疏远或排斥,而是在心态上保持一定的距离,不把他们的不当行为过分放在心上。

无翼乌火影之修罗道冲最新无翼乌火影之修罗道推荐-蚕蚕阅读

身体棒棒就是最大的财富

20、我用旧的红酒木塞,制作了这个手工作品。4:新房市场整体情况不如二手房,北京6月新房出现大规模特价房,为了抢收窗口期,新盘价格变动明显,特别是南城,从南四环开始。价格变动明显。特价有从南四环全面蔓延的迹象,单价动辄过万的降,15-20%的价格变动换来了成交量,430新政后,五环外成交除北五环少数项目外,没有明显变化。

cong“dingliunanshen”dao“wurenwenjin”,huojianhuatadaodijingliliaoshime?yuanchuang2021-08-27 18:52·fushengshuomengshuoqiyulequanzuikexidenanyanyuan,nakendingshihuojianhua。wuta,ruguomeiyoulinxinru,huojianhuadeyanyizhiluyidingbuhuizhemekanke。dangran,huizhemexiangderenbingbujinjinzhishiwangyou。gujijiulianhuojianhuabenren,dushizhemexiangde。bijingtajiuzengzaicaifangzhongshuoguo“jiehunhouwodefensidupaoguangliao”zheleihua。jinjintingzhuohuagegankaiwunaideyuqi,dajiayinggaiduhenzuoxuba!buguozuoxuguizuoxu,ruguoyaozhendelailun"fensiweishimepaowan"dehua,kendingbujinzhishilinxinrudewenti,huojianhuayinggaiyeyouxieyuanyin。kenengyouxieshuzhizhenxiangdefensihuanhuinuzuohuojianhuadao:“zheguailinxinru?zhebuguainime?fensizhisuoyipaoguang,nandaobushiyinweinibuxihuanyingyeme”?suoyihuojianhua,nicong“dahongdazi”duoluodaojintianzhege“buwenbuhuo” daozhedibu,huanzhendebuquanguailinxinru。012002nian,23dehuojianhuapingjiezhuozijideyiqiangguyong,yiranjuerandezouruliaoyanyiquan。gangkaishiyanxishi,tadeshenbianmeiyouyigezhuli。zhaoxi,shijing,tanhezuojihuquanbudushitayigerenwancheng。suiranrizishikuliaodian,danzhuizhumengxiangde“huazi”huanshihenkaixinde。zaitakanlai,zhiyaoyouxipaijiuhaoliao,leidianhekudianmeiyouduodaguanxi。kehuasuiranzhemeshuo,danmingxingzenmenengmeiyouzhuline?suoyi2nianhou,zaihuojianhuajingongneidiyulequanshi,tajiudaishangliaohaopengyoulianjunjieweitabaojiahuhang。daoliaoneidihou,lianjunjiedanqijingjirendezhize,kaishiyiluhuhanghaoyoudeyanyishengya。zaitadebangzhuxia,huojianhuayouzhushenzhu。tabujinzairihoudeyanyishengyazhongdiandingqiliaoziji“xianxiajudiyinanzhu”dediwei,huanshouhuoliaoyidabomimeidefangxin。ershuoqizhe“xianxiajudiyinanzhu”deyoulai,ziranyeyuhuojianhuacanyandexianxiajutuobuliaoguanxi。2004nian,zhuanzhanneidideyinian,huojianhuajiujieliaoquanmingxingzhenrongdeguzhuangdaju《tianxiadiyi》。zaiticaihezhenrongdeshuangzhongqushixia,guzhuangju《tianxiadiyi》haowuyiwaidebaoliao。jinguanzhegeshihou,huojianhuadeyanjibingbujingzhan,shenzhihuanbeiyezuotucao“yandetainankan”。danshipingjiezhuokusitaiwanouxiangdeyanzhi,huojianhuahuanshihuoliao。yinweijunxiushuaiqiderongmao,tahuanzhijienianyaliaonanyiliyapeng,zuoshenyudangnian“zuishuaihuameinan”xinglie。zaidangshi,zhiyaotiqihuojianhua,fensimenzonghuiluchuxingxingyan,fengkuangkuajiangzhuotadeguzhuangbanxiang。huoxushiyinweihuojianhuadeguzhuangbanxiangshizaitaiguoliangyan。jingjirenlianjunjiezhijieyiguzuoqi,geihuojianhuajieqiliao《fengchensanxiazhihongfunv》。danhenbuxing,zhebuximeiyouruxiangxiangbandedabao。yihanzhixia,lianjunjiekaishigaibianqihuojianhuadexilu,geitajieqiliaoxijupianhexiandaipian。keshitameixiangdao,zijidehaoxiongdigenxiandaipianyidianyebuxiangpei。zai2006niandao2008nian,huojianhualuxujiepailiao《zuotou》,《wudingshangdelvbaoshi》,《wushilang》,《xiandaimeinv》dengduobuxiandaipian。danrangrenshiwangdeshi,tabingweipingjiezhexiedajuzuobaohuo。yishizhijian,lianjunjiehehuojianhuaxianruliaomimangzhizhong。ruguozaizhihou,tamenhuanweizhaodaoshihedexilu。namehaowuyiwen,huojianhuadexingtukendingjiuhuibeidanwu。zaijudadeshengcunyalixia,lianjunjiejuedingguibixiandaiju,ranghaoxiongdizhongxinyanqixianxiaju。jiuzheme,huojianhuayinglailiaodareju《xianjianqixiachuan3》。fangjianyouzhemeyijuchuanwen,ruguoshuo《xianjianqixiachuan1》shixianxiajudekaiduan,name《xianjianqixiachuan3》jiushixianxiajudezuofeng。dangran,zhehuayemeishuocuo。zaihuayuyingdihuge,dareyanyuanyangmideqingqingyanyixia,《xianjianqixiachuan3》zhendebaoliao。yuzhitonglaide,shihuojianhuadedahong。jinguanzaizhebudianshijuzhong,huojianhuayiranmeiyouyanji,yiranmiantan。danzhebingbuyingxiangtadebaohuo。2011nian,zaineidifazhanbucuodehuojianhuayudaoliaotarenshengzhongdediyigeguiren-yuhong。zaitadebangzhuxia,zhegetaiwannanhaikaishijiechuqiliaoneiyudedingjiziyuan。zhihoude3nian,tajihubadaludingjinvyanyuanhezuoliaogebian。biruliushishi,biruchenqiaoen,zaibirutazhihoudelaopolinxinru。2014nian,huojianhuadeyanjidaodaliaozuofeng。zheyinian,pingjiedianshiju《zhanchangsha》,《zuomen》。tachenggongdakailiaoshilipaiyanyuandedamen,zhenzhengdechengweiliaoyimingyanyuan。kejiuzaifensiweitabaofashideyanjierjingtanshi,huojianhuayouturanyongshiligaosudazhong。tadeyanjibudawending,defenshihou。youshihoukenenghenhao,danyoushihouyoukenenghencha。jiubiruzai2015nian,tadeyanjijiuchadaoliaojidian。zheyinian,huojianhuatong“85hua”yanyuanzhaoliyinghezuoliaodaxingxianxiaju《huaqiangu》。benlai,xianxiajusuanshihuojianhuadeqiangxiang,tayinggaibuhuifanchede。danshishuizhidao,guanzhongzhecibiancongmingliao。huoxushi2015niandeliuliangyanyuantaiduoliao,shuaigeyetaishuailiao,guanzhongkaishipiekailvjingzhengshihuojianhualiao。zhemeyizhengshi,jiuzhengshichuliaowenti。zaizhegeshihou,guanzhongcaikaishiyishidao,yuanlaihuojianhuayanxizhendemiantana!tebieshizaishilipaiyanyuan“zhaoxiaodao”deduibixia,tademiantanyouweimingxian。yinweitongjuzunvzhujiaoyanjichabietaiguojuda。yishijian,guanyu“huojianhuamiantan,yanjicha”dexinwencengchubuqiong。jiulianhuojianhuabenrenyeyinweizhexiexinwenyouliaoxiexukunrao。kejinguantadeyanjibeishouguanzhongzhiyi,dianshiju《huaqiangu》huanshidabaoliao。tabujindanribofangliangchaoguo4yi,yijudaponeididianshijudanriwangluobofangliangdejilu。tahuanshineidishoubutupo200yicibofangliangdedianshiju。zaidianshiju《huaqiangu》dahuoshi,huojianhuahezhaoliyingyechenzhuozhegudongfeng,yijufeishengweineiyunannvdingliu。ruguoshuo《huaqiangu》shizhaoliyingyanyishengyadekaiduan,nametajiushihuojianhuayanyishengyadezuofeng。yinweizi《huaqiangu》zhihou,huojianhuajiuzhijieyizuobuzhen,xiaoshizaiyulequanliao。dangran,zhege“xiaoshi”bushizhenzhengde“xiaoshi”,ershishuotazaiyulequanchuxiandeyuelaiyueshaoliao。02shuoqihuojianhuadexiaoshi,wangyouyehenmimang。zaidazhongkanlai,tabingmeiyoufangenbenxingdecuowu,yemeiyouchuguihetafanga!suoyiweishime,tajiuzhemeliangliaone?qishishuoqihuojianhuade“liang”,womenbudebutiyizuilinxinru。ruguomeiyoutonglinxinrujiehundehua,huojianhuahoulaikenengbuhuizhemehu。2016nian5yue20ri,shiyigebuxunchangderizi。zheyitian,wushufensiduyinouxianghuojianhuaguanxuanlianqingerxinsuiliao。shuoshihua,yaobushihuojianhuazhudongguanxuan。dajiashizhenmeixiangdao,zheliangrenhuizaiyiqi。bijingzaidazhongkanlai,zheliangrendurenshi10nianliao,yaoshizaiyiqizaozaiyiqiliao,zenmehuanhuitongpengyouyiyang,xiangchuzhemejiune?danshuinengxiangdao,shiqingjiushizhemefanzhuanne?liangrenbujinzhijieguanxuanlianqing,huanzhijiezaiweibofabuliaojiehunshiyi。xiaoxiyifa,huojianhuadefensijiubaozhaliao。wuta,duibiyumingshengxiangdanghaode“danghongzhaziji”huojianhua,linxinrudekoubeikebuzenmehao。zaidangshi,linxinruzhengyinweitongzhoujiede“shewenshijian”beidizhi。dajiazhendehenbulijie,huojianhuaweishimeyaokanshanglinxinru。youhuojianhuadefensishenzhizhemebiaoshiguo:“neiyushimeinvmingxingliaome?weishimeyaozhaolinxinrune”?kandechulai,huojianhuadefensiduilinxinrudeeyihuanshihendade。benlaine?yibanmingxingkandaofensizhemedizhizijidelianaiduixiang,duhuikaolvyaobuyaofenshouwanhuifensiba!danhuojianhuaxiangfan,jinguanfensidizhishangliaotian,tahuanshibuguanbugu,helinxinruxiuzhuoenai。daoliaozuihou,tashenzhihelinxinrujieliaohun,shengxialiaonver。yinweizhegeshiqing,henduofensiduzifataoyanqiliaohuojianhua。biaoshi“zijiyinweilinxinru,chediduitawuganliao”。qishichuliaofensitaoyanlinxinruwai,huojianhuadegongzuorenyuanyebuzenmexihuanta。jiubiruhuojianhuadejingjirenyuhong,jiuhentaoyanlinxinru。shenzhiyinweilinxinru,yuhonghuanconghuojianhuadeshenbianlizhiliao。ruguoshuolinxinruzhishihuojianhuabian“hu”dedaohuoxian。name“duifensitaiduxiaoji,buyuanyizhudongpaixi”yinggaijiushita“liangliang”degenbenyuanyin。zaihelinxinrulianaihou,huojianhuachedituoliliaoyulequan。zhege“tuoli”bushizhitalikaiyulequan,ershizhitayuanliliaoyulequandegezhongfenxiao。takaishichuliaopaixiyiwai,buzaijierenhehuodong。meicidazhongtingdaotadexiaoxi,dushicongbierendekouzhongdezhide。dangran,ruguohuojianhuayanjihuanokdehua。natayinggaiyezhihuishi“didiao”,erbushi“wurenshi”。erzhenzhengrangtakaishiyuanlidazhongdeshi,tadeyanjibutaixing,wangyouyekaishiduitadedianyingbumaidanliao。2016nian,tatongyangmihezuo,chuyanliaodianying《nishiyingjiu》。anlishuo,lianggedingliushige7nianzaiduhezuo,yinggaihuijiqiyizhenshuihuade。danxiangfan,zhebudianyingbujinmeidaigeiliangrenrenhepuguangdu,huanranghuojianhuazaiyicidanqiliao“lanpianwang”dechenghao。zhegeshihou,ruguohuojianhuashuojijuchongfendehua,anweiyixiafensi,duifensibiaodayixiexihuan,tadeyanyizhiluhuanshinengwanhuide。danshishuizhidao,huojianhuajiushizhemeguzhine?jinguantayijingbeiheifenzuodewuyuliao,tayemeiyourenhebiaoshi。zaizhemexiaojidetaiduxia,heifenyefangqiliaozuota,zhuanergongjiqiliaoyangmi。jiuzheyang,zaiwurenguanzhudeqingkuangxia,huojianhuamanmanchenjiliaoxialai。huanshidengdao2nianhoudianshiju《ruzuochuan》bofang,tacaiyoukaishizaiyulequanyouliaoshuihua。2018nian,huojianhuatongzhouxunzhuyandedazhizuodianshiju《ruzuochuan》zhongyushangyingliao。duiyuzhebudazhizuo,wangyoubenlaiqidailiaohenjiu。danshisuizhuogongtingju《zuozuogonglue》derebo,guanzhongquanbudubeixiyinliaoguoqu。yishizhijian,《ruzuochuan》jiuzhemeliangliaoxialai。jinguanzhebujudezhuyanshiyinghouzhouxunhexianxiajudiyinanzhu,zhebujuyemeinenghuoguo《zuozuogonglue》。keyizhemeshuo,benlaidasuankaozhebujufanhongdehuojianhua,chedideshibailiao。ruguoshuojinjinmeifanhongyejiusuanliao。kongbudeshi,tahuanzaoshoudaoliaomengliederenshengongji。yinweitong《zuozuogonglue》linieyuandeduibi,huojianhuadeyanjibeipengjideyiwenbuzhi。zaiwangyoukanlai,huojianhuachudaozhemeduonianzhiyou2014nianshiyanjizaixiande。zhiyuqitashike,yanjiduhenyiyannanjin。huoxushibeiwangyoupengjidehenliao,bolixindehuojianhuachedishoubuliaoliao。2018nian,tazhengshixuanbuweibodengshejiaoruanjian,kaiqiziji“foxingyanxi”deshengya。duiyuhuojianhuadezhenaifenlaishuo,zhewuyishijianjiqishangxindeshi。wuta,benlaizijideouxiangjiubuzenmeyingye。zhemeyituichu,bujiushigengchenjiliaome?kejiusuanfensiqianlanwanzu,huojianhuayemeifangqizijidexiangfa。huantuideweibohuanshituiliao,gaixiaoshiderenyinghuanshixiaoshiliao。jianjiandi,bieshuofensiliao。jiusuanshihuojianhuadepengyou,duzhaobudaotaliao。jinguanzai2019nian,tazaicitongyangmihezuoliaodianshiju《zhumengqingyuan》。danzhebushuangdingliudeminguoxibujinmeiyoudabao。xiangfan,tahuanhenhu。ruguoyidingyaolaixingrongta“hu”daoliaoshimechengdudehua,najiushi“chuliaofensiyiwai”,meirenzhidaozhebuxi。huoxushibeizhebeixideshoushilvdajidaoliao,huojianhuaheyangmiduchenjiliaoyiduanrizi。dantongyangmideduanzanxiuxibuyiyang,huojianhuashizhenzhengkaiqiliaozijide“xiuxizhilv”。2019nian2021nian2nian,tameizaipairenhexi。chuliaoxifenyiwai,tayemeizairenheshejiaohuodong。suoyiyishizhijian,huojianhuajiuzhemexiaoshizailiaodazhongyanzhong。dengdaodajiazaixiangqitashi,huanshizaipengyoushaichudezhaopianzhong。kanzhuozhaopianzhonghuojianhuakaixindaxiaodemoyang,wangyouzhendehengankai。wuta,zaiyiqianyanxishi,huojianhuadexiaorongzongshihenmianqiang。yinweitabuxihuanxiao,bushanyancideyuangu,wangyouhuanzengzuozuotashi“laoganbu”。danshishuizhidao,sixiadehuojianhuanengxiaodezhemekaixinliao。suoyihuojianhua,shizhendehenfoxinga!tayinggaishizhendemeiyoushiyexinliao,kenengbiqishiyelai,tagengxihuanshenghuoba!bijingzaizhiqianjiuyouwangyoubaoliao:“linxinruzengbizhuohuojianhuayanxi,danshichuyuduijiatingdekaolvhezhaohu,tahuanshijujueliao”。shuoshihua,ruguohuojianhuazhendemeiyouyanxideyuwanghua。natahuanshihaohaozhaogujiatingba!yaozhidao,ruguomeiyouyanxideyuwang,shiyanbuhaoyibuxide。suoyiyuqilangfeijingliheshijianlaichuyanyibulanpian,huanburuzhuanxinjiating,chongaiqinv。03kenengduihenduorenlaishuo,huojianhuashibayifuhaopaigeidalanliao。danshiduiyuhuojianhuabenrenlaishuo,tabuzhemerenwei。zaitakanlai,shiyeyongyuanshimeiyoujiatingzhongyaode。jinguanzaizhezhiqian,taweiliaoshiyeyuanzoutaiwan。danzhebingbuyiwei,shiyejiushitarenshengzuizhongyaodeshi。zaimeijiehunzhiqian,shiyeyinggaishihuojianhuadequanbu。danjiehunzhihou,qinvjiushihuojianhuadequanbuliao。qishizheyangyetinghao,biqizuoyigehaoyanjideyanyuanlai,huojianhuakenenggengshihezuoyigehaozhangfu,haoairen。changfunenglifangmian,bainianrenshou2022niansanjidumohexin、zonghechangfunenglichongzulvfenbiewei84.77%、124.50%,danqi2022niandiyijiduhedierjidufengxianzonghepingjiweiClei,weichangfunenglibudabiaoxianqi。gaigongsibiaoshi,fengxianzonghepingjijieguowei C lei,zhuyaoyouyucaozuofengxiandegongsizhilifangmian。

不(叠耻)假(闯颈补)思(厂颈)索(厂耻辞)地(顿颈)回(贬耻颈)答(顿补),足(窜耻)以(驰颈)证(窜丑别苍驳)明(惭颈苍驳)她(罢补)的(顿别)爱(础颈)国(骋耻辞)之(窜丑颈)心(齿颈苍)。

产别苍飞别苍虫颈苍测耻补苍濒补颈锄颈辩耻补苍飞别颈产补辞诲补辞【濒耻锄丑辞苍驳肠丑别苍产补辞】【锄丑辞苍驳丑耻补飞补苍驳】【蹿补箩颈补锄颈虫耻苍】(虫颈补苍驳虫颈虫颈苍测耻补苍蹿耻锄补颈飞别苍锄丑补苍驳尘辞飞别颈)。飞别颈迟颈蝉丑别苍驳飞别苍锄丑补苍驳办别诲耻虫颈苍驳,虫颈箩颈别办别苍别苍驳肠耻苍锄补颈谤耻苍蝉别,辩颈苍驳濒颈锄丑颈测耻别诲耻,箩颈苍驳辞苍驳肠补苍办补辞!别谤箩耻苍箩颈补肠丑补辞50飞补苍测耻补苍诲别飞别苍箩颈别惭9产颈补辞虫颈补苍肠丑耻蝉丑颈锄耻诲别丑辞耻箩颈苍,6测耻别驳辞苍驳箩颈补辞蹿耻1.72飞补苍濒颈补苍驳,濒颈补苍虫耻蝉补苍驳别测耻别飞别苍诲颈苍驳驳耻辞苍别颈诲补虫颈苍驳厂鲍痴虫颈蹿别苍蝉丑颈肠丑补苍驳测颈箩颈蝉丑辞耻箩颈补50飞补苍测颈蝉丑补苍驳虫颈补辞驳耻补苍。

『戴(Dai)上(Shang)耳(Er)机(Ji) 原(Yuan)地(Di)起(Qi)飞(Fei)』HiVi·惠(Hui)威(Wei)试(Shi)音(Yin)·发(Fa)烧(Shao)音(Yin)响(Xiang)煲(Zuo)机(Ji)试(Shi)音(Yin)天(Tian)碟(Die)10CD

然而,直到2022年6月,在佐治亚州建设高铁的计划才被再次提及。FR4到底是指什么材料?——我对PCB设计的认知提升过程【10】2023-07-28 23:22·硬十PCB(Printed Circuit Board,印刷电路板)是一种用于连接和支持电子元器件的基板。它们广泛用于各种电子设备和系统中。根据不同的标准和应用,PCB可以根据多个方面进行分类。其材料可以说非常丰富。由于大多数工程师都是关注设计,但是随着结构复杂性增加,信号完整性相关问题跟材料相关性,散热的挑战。工程问题需要工程师更多地关注PCB的材料。按照PCB材料的结构特性分类:刚性PCB:使用刚性材料(通常是玻璃纤维增强的环氧树脂)制造的PCB。它们通常用于大多数电子设备中,如计算机、电视和家用电器。柔性PCB:使用柔性材料(如聚酰亚胺)制造的PCB。它们可以在弯曲和弯折的情况下使用,适用于特定形状和空间限制的设备,如折叠手机、相机等。刚性-柔性PCB:结合了刚性和柔性PCB的特点,常用于需要连接和支持在不同部分之间移动的组件。软硬结合板(刚柔板)是什么?FPC与PCB的诞生与发展,催生了软硬结合板这一新产物。因此,软硬结合板,就是柔性线路板与硬性线路板,经过压合等工序,按相关工艺要求组合在一起,形成的具有FPC特性与PCB特性的线路板。软硬结合板(刚柔板)生产流程:因为软硬结合板是FPC与PCB的组合,软硬结合板的生产应同时具备FPC生产设备与PCB生产设备。首先,由电子工程师根据需求画出软硬结合板的线路与外形,然后,下发到可以生产软硬结合板的工厂,经过CAM工程师对相关文件进行处理、规划,然后安排FPC产线生产所需FPC、PCB产线生产PCB,这两款软板与硬板出来后,按照电子工程师的规划要求,将FPC与PCB经过压合机无缝压合,再经过一系列细节环节,最终就制程了软硬结合板。软硬结合板加工难度大,细节问题多,在出货之前,一般都要进行全检,因其价值比较高,以免让供需双方造成相关利益损失。软硬结合板(刚柔板)优点与缺点:优点:软硬结合板同时具备FPC的特性与PCB的特性,因此,它可以用于一些有特殊要求的产物之中,既有一定的挠性区域,也有一定的刚性区域,对节省产物内部空间,减少成品体积,提高产物性能有很大的帮助。缺点:软硬结合板生产工序繁多,生产难度大,良品率较低,所投物料、人力较多,因此,其价格比较贵,生产周期比较长。首先我们看看一般PCB板的组成方式多层PCB是由一个双面覆铜板,两边不断的压合半固化片和铜箔来实现的。双面覆铜板,中间是介质层,半固化片也是介质层。半固化片"Prepreg" 是 "Pre-impregnated"(预浸渍)的英文缩写,是一种片状粘结材料,通常用于PCB的制造过程。Prepreg是一种复合材料,由树脂和玻璃纤维(或其他增强材料)构成。在制造PCB的过程中,预先浸渍树脂的玻璃纤维布或薄片被称为Prepreg。制造PCB的主要步骤之一是层压,其中多层预先浸渍树脂的玻璃纤维布在高温和高压下被压合在一起,形成多层的PCB结构。在此过程中,预先浸渍的树脂在高温下融化,然后在冷却过程中重新凝固,以形成坚固的粘结材料,将玻璃纤维层黏结在一起,并形成一个整体的PCB结构。Prepreg的使用使得制造复杂多层PCB变得更加容易和高效。它可以确保在层压过程中树脂在适当的位置浸透玻璃纤维,从而实现均匀的树脂分布和良好的粘结性能。这有助于提高PCB的机械强度、电气性能和可靠性。总的来说,Prepreg是PCB制造过程中关键的材料之一,它为多层PCB的制造提供了重要的基础和保障。按照基板材料的耐燃等级进行分类我们经常说的PCB的材料“FR-4”是一种耐燃材料等级的代号,它所代表的意思是树脂材料经过燃烧状态必须能够自行熄灭的一种材料规格,它不是一种材料名称,而是一种材料等级,因此目前一般电路板所用的FR-4等级材料就有非常多的种类,但是多数都是以所谓的四功能(Tera-Function)的环氧树脂加上填充剂(Filler)以及玻璃纤维所做出的复合材料。FR-4水绿玻纤板 黑色玻纤板,都具有耐高温、绝缘、阻燃等功能所以大家在选择材料的时候一定要搞清楚自己需要的材料要达到什么特点为。FR-4是一种常用的PCB基板材料,它是“火焰阻燃”(Flame Retardant)级别为4的玻璃纤维增强环氧树脂材料的简称。解释一下其中的意思:火焰阻燃(Flame Retardant):火焰阻燃是指材料在受到火焰作用时能够减缓火焰的传播速度或自熄灭,从而减少火灾的危险。在电子设备中使用的材料,尤其是PCB基板材料,需要具有良好的阻燃性能,以确保设备在异常情况下不会因火灾而引发更严重的问题。FR-4级别为4:FR-4被分为不同级别,其中级别4代表了一种具有较高阻燃性能的材料。根据国际电工委员会(IEC)标准,FR-4级别为4表示材料的垂直燃烧速率小于或等于30毫米/分钟。FR-4级别为4的材料在阻燃性能上比较可靠,被广泛用于电子设备制造。因此,FR-4这个名词是对一类玻璃纤维增强环氧树脂材料的简称,它是一种常见的、可靠的、具有良好阻燃性能的PCB基板材料。由于其性能稳定和生产成本相对较低,FR-4材料在大多数通用电子设备的制造中得到广泛应用。所以看到阻燃等级并不特指某一个固定的材料。玻纤布基板如前面所述,最常用的PCB基板是玻纤布基板,由玻纤和树脂,再加固化剂组成。我们按照材料种类可以看下:按树脂不同来分。树脂A. 功能:作为铜箔与玻璃纤维布之间的粘合剂 。B. 特性:抗电气性、耐热性、耐化学性、抗水性。树脂的种类:由于树脂种类有多种,所以决定了我们材料的多样性。PCB行业中常用的树脂体系有以下几种:酚酫树脂板环氧树脂板聚脂树脂板BT树脂板(一种特殊的高性能环氧树脂基板 )PI树脂板(聚酰亚胺树脂 )三嗪和/或双马来酰亚胺树脂玻璃纤维布是一种经过高温融合后冷却成一种非结晶态的坚硬的无机物,然后由经纱,纬纱纵横交织形成的作为基板结构中补强材料(类似于人体的骨骼结构)。可以作为补强材料的有:纤维素纸、E-玻璃纤维布、S-纤维布等。玻纤布的纹理方向会对PCB的阻抗产生影响。在制造多层PCB时,使用玻纤布作为基板的增强材料。玻纤布通常以不同的方向叠加在一起,这些方向被称为纹理方向。阻抗是电路板传输信号时的电阻性质。阻抗值的准确性对于高速和高频电路的性能至关重要。纹理方向会影响PCB的介电性能,从而影响阻抗。主要影响有以下几点:介电常数:玻纤布的纹理方向会影响PCB材料的介电常数,而介电常数是计算阻抗的重要参数。纹理方向不同,玻纤在材料中的分布也会不同,从而导致介电常数的变化。损耗:玻纤布的纹理方向也会影响PCB材料的损耗特性。材料的损耗会使信号在传输过程中发生衰减,并且损耗也与信号频率有关。极化效应:在某些情况下,玻纤布的纹理方向可能导致极化效应,即材料在电场中出现极化现象。这种极化现象也会对阻抗产生一定的影响。由于纹理方向的影响,PCB设计中需要考虑和控制玻纤布的叠层方向,特别是在高速和高频电路的设计中。设计人员通常会根据需要选择合适的玻纤布纹理方向,以确保PCB的阻抗值在规定范围内,并满足特定应用的性能要求。固化剂DICY型(双氰胺,适用于一般材料,只需加入5%即可反应,极性强,不耐热,市场占有率90%)PN型(酚醛树脂,适用于无铅材料,HTG,需加入20~30%反应,极性不强,耐热性好,市场占有率10%)如果我们按照PCB的基板材料分类:有机基板:使用有机材料,如FR-4(玻璃纤维增强环氧树脂)制造的PCB。无机基板:使用无机材料,如陶瓷制造的PCB。无机基板具有更好的散热性能,适用于高功率和高温应用。选择板材,我们需要考虑SMT带来的影响无铅化电子组装过程中, 由于温度升高,印刷电路板受热时发生弯曲的程度加大,故在 SMT 中要求尽量采用弯曲程度小的板材,如 FR-4 等类型的基板。由于基板受热后的胀缩应力对元件产生的影响,会造成电极剥离,降低可靠性,故选材时还应该注意材料膨胀系数,尤其在元件大于 3.2×1.6mm 时要特别注意。表面组装技术中用 PCB 要求高导热性,优良耐热性(150℃,60min)和可焊性(260℃,10s),高铜箔粘合强度(1.5×104Pa 以上)和抗弯强度(25×104Pa),高导电率和小介电常数、好冲裁性(精度±0.02mm)及与清洗剂兼容性,另外要求外观光滑平整,不可出现 翘曲、裂纹、伤痕及锈斑等。前期系列内容:推荐书籍《硬件十万个为什么(开发流程篇)》无翼乌火影之修罗道冲最新无翼乌火影之修罗道推荐-蚕蚕阅读

中新网长治7月4日电 题:夜经济点燃山西黎城烟火气 释放消费新活力

发布于:游仙区
声明:该文观点仅代表作者本人,搜狐号系信息发布平台,搜狐仅提供信息存储空间服务。
意见反馈 合作

Copyright ? 2023 Sohu All Rights Reserved

搜狐公司 版权所有